Bulletin of the American Physical Society
APS March Meeting 2024
Monday–Friday, March 4–8, 2024; Minneapolis & Virtual
Session NN00: Virtual Poster Session III (6:30am8:00am CST)Poster Undergrad Friendly Virtual Only

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Chair: Abdullah AlShuaibi, Cornell University; Apurba Paul, University of Notre Dame; Jonte Hance, Newcastle University 

NN00.00001: SOFT MATTER PHYSICS


NN00.00002: Driven Shock in Three Dimensions: Euler Equations Versus Molecular Dynamics, and NavierStokes Equations AMIT KUMAR, Rajesh Ravindran Isotropic and continuous localised perturbations in a stationary gas, created by an external point source, cause a spherically symmetric shock wave with the energy E(t) increasing in time t as E(t)∽ t^{δ}, where δ≥0. The analytical solution of the Euler equation providing the spatiotemporal behavior of the shock wave, is a classic problem in gas dynamics. The exact solution shows that the asymptotic behavior of nondimensionalised thermodynamic quantities obey power law behavior in rescaled distance near the shock center with the exponents independent of δ. However, using Event Driven Molecular Dynamics Simulations, we find that the exact solution does not match with EDMD results, anywhere, mainly in terms of the power law exponents near the shock center. We show that this mismatch is due to ignoring the contribution of heat conduction and viscosity terms, and the mismatch between theory and numerics can be resolved by taking into account the NavierStokes equation. We showed that the direct numerical solution of NavierStokes equation captures these observed power law exponents in the EDMD simulations indicating the significance of viscosity and heat conduction in shock problems. 

NN00.00003: Harmonic Mastery in TimeModulated Linear Elastic Unit Cells Pravinkumar R Ghodake In a recent scholarly inquiry led by Ghodake (2023), the primary focus was the exploration of nonlinear responses within timemodulated linear materials. This investigation was primarily motivated by the desire to gain a deeper comprehension of the intricate interactions involving poweramplified elastic waves, which hold significant utility in the context of nonlinear ultrasonic testing for applications related to structural health monitoring. This study centers on harnessing the harmonic manipulation capabilities of a novel unit cell, consisting of a timeindependent linear material matched in impedance, sandwiched between two timemodulated linear materials. Through numerical experiments employing finite element methods, our investigation reveals the unit cells' versatile harmonic manipulation potential within phononic crystals. The numerical findings vividly depict how changes in timemodulation frequency impact the presence, absence, and distribution of harmonic energies. This intricate phenomenon arises from the interplay between linear and nonlinear elastic wave scattering due to time modulation, offering fresh insights into wave propagation dynamics complexities. 

NN00.00004: Effective Viscosity and Mobility of Hot Particles in a Viscous Suspension Osher Arbib, Naomi Oppenheimer


NN00.00005: STATISTICAL AND NONLINEAR PHYSICS


NN00.00006: How disorder impacts information content in continuous attractor networks Tobias Kühn, Rémi Monasson Attractor networks are a theme with long tradition to model information storage in the brain. Continuous attractor neural networks (CANN), in particular, have been employed to describe the storage of information about space and orientation. However, it stays controversial how useful this paradigm really is to explain actual processes, for example, in mammals, the representation of space in grid and place cells in the entorhinal cortex and the hippocampus, respectively. 

NN00.00007: Exploring Phase Transitions in OneDimensional Diluted PowerLaw XY Spin Glass: A Numerical Investigation Ramana Bharadwaj Vedula, Auditya Sharma, Michael Moore For decades, the behavior of finitedimensional spin glasses at low temperatures has been a subject of ongoing debate. The physics of spin glasses has been described using two primary frameworks: the replica symmetry breaking (RSB) picture and the droplet picture. In this poster presentation, we focus on our recent work investigating the AT line in the 1D powerlaw diluted XY spin glass model. Initially, we describe the MCMC methods employed, including a specialized heatbath algorithm tailored for XY spins, showcasing its novelty. Our study reveals clear evidence of an AT line for σ=0.6 in the meanfield regime. For σ=0.75, finitesize scaling studies support the presence of an AT transition, but for σ=0.85, there is no evidence of a transition. Furthermore, we investigated these systems at a fixed temperature while varying the field and discovered that at both σ=0.75 and at σ=0.85, there is evidence of an AT transition! Additionally, we studied a new quantity R and its scaling with system size N for different values of σ. We observe an increasing trend in R with increasing N for σ values greater than 2/3, while for σ=0.6, R decreases with N. This shift in the trend of R with N results from the absence of a phase transition for σ>2/3 in the presence of a magnetic field. Combining our simulation results, we argue that even a slight amount of external magnetic field leads to the destruction of the spin glass phase in shortrange models, aligning our findings more with the droplet picture than the RSB picture. 

NN00.00008: BIOLOGICAL PHYSICS


NN00.00009: The Bipolator: A SelfOrganized Spindlelike Bipolar Microtubule Assembly Exhibiting Oscillatory Behavior wei xiang chew, francois nedelec, thomas surrey The mitotic spindle, a selforganized bipolar assembly of microtubules and crosslinking motors, is characterized by a fluxing mixedpolarity nematic center and radially polar poles (aster). This study explores the fundamental components and mechanisms necessary to establish such a structure. Using computer simulations, we reveal that dynamical microtubules growing from persistently microtubuleassociated nucleating seeds combined with opposing motors, are sufficient to organize microtubules into bipolar assemblies in the absence of any chromosomes, centrosomes or a nucleation gradient. At steadystate, the microtubules within this structure are predominantly transported by plus motors, switching orientation at the poles before transiting towards the opposing pole, hence demonstrating oscillatory behavior. This behavior depends on microtubule dynamic instability, seed size, and the specific type of minusend motors used. Intriguingly, the poletopole distance varies with the number of minusend motors, a phenomenon previously observed in spindles in cells. The control of the length of the Bipolator can be explained considering an equilibrium of microtubule flux across the pole. This study illuminates the fundamental dynamics of a bipolar assembly, thereby deepening our understanding of the bipolarity of a mitotic spindle. 

NN00.00010: Bacterial operons response dynamics to genomewide stresses. Rahul Jagadeesan, Andre Sanches Ribeiro Bacterial gene networks rely on operons to coordinate activities involving multiple genes. In Escherichia coli, operons have internal promoters that allow regulating downstream genes, independently from upstream genes. We studied genomewide stress responses in this organism targeting two global transcription regulators. We show that premature terminations of transcription elongation and internal promoters play a major role in operons, causing differences between gene response strengths to follow sinusoidal patterns that are influenced by positive supercoiling buildup. We further observe the same using data on E. coli cells subject to other stresses, as well as in Bacillus subtilis, Corynebacterium glutamicum, and Helicobacter pylori. Overall, our results suggest that internal promoters assist operons by compensating for premature terminations. This finding further opens new avenues by suggesting a new means to achieve complex dynamical behaviors in synthetic genetic circuits. 

NN00.00011: Linking rate based and spiking models: A Quest towards biologically relevant neural systems Aiswarya PS The brain is made of billions of neurons connected together to form networks. These networks give rise to various activities reflected in a range of behaviors. The branches of neuroscience have accomplished tremendous feats to explain these behaviors and shed light on how the brain works. However, up until now, neuroscience has been very descriptive. This is unfortunately not enough, and understanding the brain demands more. A multidisciplinary approach combining theoretical and experimental methodologies is used to understand the neurological and computational underpinnings of this wide variety of behaviors. Neural network dynamics is one such approach that deals with understanding how neural circuitry generates complex activity and accounts for most of the specific characteristics of the neuron and its responses. The dynamics of the brain are multiscale, ranging from ion channels and synapses at the molecular level to emergent behavior, like oscillations at the scale of the entire brain. The challenge, therefore, becomes how to create predictions regarding brain dynamics while simultaneously incorporating these various dimensions. 

NN00.00012: CHEMICAL PHYSICS


NN00.00013: Molecular structure, vibrational spectral assignments, UVVis and thermodynamic properties of C_{62}O_{2}H_{14} based on DFT calculations Ongun Ozcelik, Meryem Evecen Theoretical investigations on the C_{62}O_{2}H_{14} including fulleron were done to study the structural, spectroscopic (IR, UV) and thermodynamic properties. The geometry optimization was performed at the B3LYP level using the 631G (d) basis set. The vibrational and UVVis spectral values were obtained and the data were compared with similiar theoretical values. Molecular electrostatic potential (MEP) analyses were performed to predict the reactive sites of the molecule. The thermodynamic properties of the compound at different temperatures have been determined and correlations between heat capacity, entropy, enthalpy and temperature have been done. 

NN00.00014: Completeness of representations in atomistic machine learning Jigyasa Nigam, Michele Ceriotti, Sergey Pozdnyakov, Kevin K HugueninDumittan The problem of obtaining a comprehensive and symmetric representation of point particle groups, such as atoms in a molecule, is crucial in machinelearning techniques for physical problems as it underpins the capacity of models to accurately reproduce physical relationships while being consistent with fundamental symmetries and conservation laws. 

NN00.00015: Transition metal metal carbide decorated Ndoped carbon framework as efficient dual MottSchottky electrocatalysts for water splitting Gokul Raj Transition metal carbides (TMCs) have garnered significant attention as effective electrocatalysts for the hydrogen evolution reaction (HER), offering a highly active and stable alternative to precious metals like platinum, because of their dband electronic structure resembling that of platinum. In this study, we address the challenge of developing a toptier bifunctional electrocatalyst for efficient water splitting by employing a dual transition metal approach to electronically modify bimetallic carbides. Here, we have designed a composite structure through an insitu fabrication process, featuring Ndoped carbon nanotubes (CNT) and graphene, which serve as anchors for Co/MoC, Co/WC, and Co/VC. This integrated pyrolysis technique promotes synergistic interactions among these components and creates dual MottSchottky junctions, resulting in a bifunctional catalyst capable of catalyzing both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) with exceptional activity in both acidic and basic environments. Furthermore, it demonstrates excellent performance in water splitting under basic conditions, requiring a relatively low cell voltage of approximately 1.686 V to generate a current of 10 mA/cm² while maintaining good stability. This superior performance is attributed to the cooperative electron transfer between the Co and MoC moieties and the defects induced by nitrogen doping in the graphene/CNTbased conductive network, distinguishing it from other recently reported Mobased carbide materials. 

NN00.00016: ATOMIC, MOLECULAR, AND OPTICAL PHYSICS


NN00.00017: Laser protection of Rydberg atoms over the gate operation Mohammadsadegh Khazali, Hossein Abedi Laserexcited Rydberg atoms have shown great potential for various applications in atomic [17] and photonic [815] quantum technologies. One commonly used method for Rydberg quantum gates is the πgapπ scheme, where atoms are left in Rydberg states for a gap period of time while other atoms are under laser rotations. However, it has been observed that for highly excited Rydberg atoms, the subsequent deexciting π pulse cannot fully return the Rydberg population to the qubit basis. This limits the use of Rydberg states with larger interaction to loss ratio.


NN00.00018: Theoretical Investigation of fine structure and wavefunctions of Tantalum atom for 5d^{3}6s^{2} and 5d^{2}6s^{2}6p configurations. Rimsha Shaikh Wave function contains all the information of electrons and defines the probability of a particle to be in various Energy Eigenstates. The ground state wave function of the quantum manybody system is a complicated task to calculate. Tantalum belongs to d block element, and it has open d shell configuration. This study is an attempt to determine two electron shell configurations of Ta I, 5d36s2 and 5d26s26p. Term symbols, fine structure, total angular momenta, coefficient of fractional parentage and coupled wave functions for two configurations of 5d36s2 and 5d26s26p of Ta I have been investigated. RussellSaunders coupling scheme or LS coupling scheme has been used to obtained 39 term values and 95 fine levels. The minimum value of total angular momentum J is 1/2 and maximum 11/2 for both configurations. Total 120 microstates are determined for configuration 5d36s2.81 coupled wave functions along with their coefficient of fractional parentage are reported for Ta I. These wave functions are important to calculate several spectroscopic quantities i.e., probability density, lifetime, energy, etc. 

NN00.00019: CONDENSED MATTER PHYSICS


NN00.00020: Dissipativefree chiral edge transport in stacked (Al/Ni)_{10} multilayers Mikhail Belogolovskii, Ivan P Nevirkovets Using the phasesensitive Josephson interferometry technique, we demonstrate signatures of nontrivial edge modes in stacked multilayers S(NF)_{10}NI(NF)_{10}NS formed by conventional normal (N = Al) and magnetic (F = Ni) nanometerthick metallic films, an insulating interlayer (I = Al oxide), and two superconducting (S = Nb) electrodes. The main findings are (i) strongly upwardly shifted periodic SQUIDlike dependences of the maximum supercurrent on the probing inplane magnetic field instead of conventional Fraunhofer patterns with nodes and (ii) h/e period of the oscillations rather than the superconducting h/2e flux quanta. Replacing the I layer with a S′IS′ junction (S′ is an ultrathin Nb layer) led to the restoration of Fraunhofer behavior, indicating the transformation of supercurrent into hybrid electronhole modes upon contact of the superconducting S′ plane with an (NF)_{10}N multilayer. Analyzing the data obtained, we come to the conclusion that the (NF)_{10}N multilayers under study are threedimensional electronic systems, possessing gapped bulk and side surface states with quasionedimensional backscatterfree ingap hinge modes propagating unidirectionally and possibly topologically protected. Two probable origins of the observed phenomena are discussed  a fully quantum scenario and that based on nonHermitian physics in nonconservative systems. 

NN00.00021: Topological Phases in Quasi One Dimensional Material TaSe_{3} under Pressure Anita G Francis, Janaky Sunil, Swapan K Pati TaSe_{3} is a quasi 1D material, which is a superconductor at very low temperatures and was recently characterized as a Topological Insulator (TI). The existence of nontrivial topology in an intrinsically superconducting material might make the realisation of Majorana Fermions possible, thus advancing the efforts in the field of quantum computing. We aim to understand the effect of hydrostatic pressure on the electronic and structural properties of TaSe_{3}, using first principles calculations combined with Raman spectroscopy. Our calculations reveal that TaSe_{3} undergoes two topological phase transitions under the application of pressure, around 5 GPa and 7 GPa. The first transition occurs from a weak topological insulator phase to a strong TI phase, while the second transition, around 7GPa, is from a strong to weak topological insulator phase. The weak TI hosts an even number of Dirac cones, which annihilate in the presence of strong disorder, while the strong TI phase hosts an odd number of Dirac cones on all its surfaces, which are protected against disorder by Time Reversal Symmetry. The Dirac cone in the strong insulating phase and the corresponding Fermi arc are also plotted, which shows the linear dispersion of the Dirac fermions. Our study provides a careful analysis of the topological nature of TaSe_{3} at ambient pressure and reveals the role of hydrostatic pressure in tuning the electronic bands and the surface spectrum of a Topological Insulator. 

NN00.00022: Spin fluctuation observed by ^{75}As NMR relaxation rate in ironpnictide superconductor Ba_{0.66}K_{0.34}Fe_{2}As_{2 }: Comparison with nematic fluctuation Yoshihiko Ota, Taku Matsushita, Shigeyuki Ishida, Akira Iyo, Hiroshi Eisaki, Yoshiaki Kobayashi Spinecho decay rate 1/T_{2} was measured to investigate the lowenergy spin fluctuations in the holedoped iron superconductor Ba_{0.66}K_{0.34}Fe_{2}As_{2}. In a wide temperature range, the relaxation curves are wellfitted by considering the Lorentzian and the Gaussian decay components, and the relaxation rates 1/T_{2L} and 1/T_{2G} were obtained. In general, the 1/T_{2L} is described by contributions of longitudinal magnetic fluctuations along the applied field and transverse one as the nuclear spinlattice relaxation rate 1/T_{1}[13]. We elucidated that the 1/T_{2L} is wellscaled with the 1/T_{1} , indicating that the contribution of 1/T_{1 }is dominant. Both 1/T_{2L} and 1/T_{1 }increase on cooling toward the superconducting temperature T_{c}, implying the development of magnetic fluctuations. The magnetic anisotropy observed both in 1/T_{2L} and 1/T_{1 }suggests that the striped magnetic fluctuations develop toward T_{c}. Below 100 K, the magnetic anisotropy in 1/T_{2L} is slightly smaller than that in 1/T_{1}, possibly indicating slight longitudinal magnetic fluctuations. On the contrary, the Gaussian component 1/T_{2G }is temperatureindependent, resulting from the direct dipole interactions between ^{75}As nuclear spins. The comparison between the 1/T_{2L}T monitoring spin fluctuations and the nematic susceptibility suggests a possible coupling between spin and orbital fluctuations, but the coupling is weaker than that in electrondoped systems (e.g. LaFe_{1x}Co_{x}AsO and Ba(Fe_{1x}Co_{x})_{2}As_{2}))[46]. The origin of the weaker coupling in a holedoped system Ba_{0.66}K_{0.34}Fe_{2}As_{2} will be discussed. 

NN00.00023: Fractional Quantization Interpretation for the PhaseLocking dynamics of drivenSuperconductive Josephson ac effect Techun Wang This report proposes a quantization interpretation on the Macroscopic quantum dynamics of driven ac Jesephson effect. A discussion is made to compare the socalled classical resonance and the Macroscopic dynamics of of Josephson oscillation of the phase difference across the junction. A collective quantum phase locking dynamics, with integer or fractional winding numbers, is proposed to unify the Shapiro steps as a mechanism of quantization. The proposed fractional quantization of macroscopic quantum phase locking may provide a new unifying thinking on the Quantized Hall Effects including IQHE and FQHE. 

NN00.00024: Poster:Twist angle monitored inhomogeneous magnetism in a van der Waals itinerant moiré ferromagnet SARANSHA MOHANTY, Weibo Gao, Pritam Deb Abstarct: Two dimensional (2D) van der Waals (vdW) moire magnets are the next generation quantum materials which hold the possibilities to unlock unprecedented properties in the field of twistronics and spintronics on account of their strong electron correlations. Essentially, the strong electron correlations in twisted geometries of vdW layers have a central role in of manifestation of unusual magnetic properties such as skyrmions, noncollinear magnetic textures, moire Zeeman effect and many more. Hence, identification of ideal materials is of great importance for realization of such exotic quantum phenomena. Here, we showcase a new quantum mechanical phenomenon of twist regulated onsite magnetism in vdW bilayer consisting nonmagnetic 1TNbSe_{2} and ferromagnetic 1TVSe_{2} monolayers at various twist angles. In particular, we observe appearance of inhomogeneous mixture of quenched and augmented magnetic moments per V and Nb atoms. The inhomogeneity in the magnetic moment per V and Nb atoms is strongly influenced by the twist angles, depicting a significant variation of the variance of the magnetic moments with twist angles. Moreover, we find prominent flat bands emerging at higher twist angles making the system more localizedlike allowing for such inhomogeneous behavior. The studied systems satisfy Stoner criterion for ferromagnetism and the findings reveals that local moments of the system can suitably be tuned with twist angles. 

NN00.00025: Edible biomaterial based memristive devices for nonvolatile memory design Dimpal Kumari, Soumya J Ray With the development of technology, electronic waste has become an undesirable burden on our environment due to the extreme usage of perilous materials. Therefore, it is very beneficial to use biomaterials for the fabrication of electronic devices that are biocompatible, environmentally benign, nontoxic, etc. Resistive Random Access Memory(RRAM) is one of the most promising memristive devices due to its simple metalinsulatormetal (MIM) structure, having high speed, ultimate scalability, low power consumption, capability of numerousbit switching, and CMOS compatibility. Edible biomaterials like egg albumen(sources of protein), eggshell (Calcium carbonate), inner peel of citrus fruits (source of pectin/polysaccharide), Potato (source of starch), crabs, prawns (source of chitosan), etc. are most promising components for the fabrication of BioReRAM. This study foregrounds the extraction and fabrication of Ag/Egg albumen/ITO and Ag/Eggshell powder/ITO devices which work on the principle of resistive switching. Further, we have explored the structural and conduction mechanism differences/similarities between the above two systems. Characterizations like FESEM, FTIR, UVvisible spectroscopy, electrical IV measurements, IV loglog plot, and endurance (I_{On}/I_{Off}) behavior analysis have been done for both devices. This demonstrates that Egg albumen and Eggshell both are the most promisable, robust as well as ecofriendly candidates for the nextgeneration memory applications. 

NN00.00026: An Effective Supramolecular Zinc Metallohydrogel based RRAM Device for Inmemory computing Application ARPITA ROY, Subhendu Dhibar, Bidyut Saha, Soumya J Ray Supramolecular gels are versatile materials that possess smart properties. They are used in various industries such as sensors, cosmetics, foods, nanoelectronics, logic gates.These gels are formed through the combination of hydrogels and supramolecular chemistry. In this work, we have developed a wellorganized and efficient method to rapidly synthesize a supramolecular zinc based metallohydrogel. This metallohydrogel is prepared by using pentaethylenehexamine as a low molecular weight gelator in water at room temperature. Here, we have fabricated a zinc metallohydrogel based Schottky diode device in a lateral metalsemiconductormetal geometry to explore its charge transport behavior^{1,2,3}. Here, zinc metallogel based RRAM (Resistive random access memory) device have showed a proper bipolar resistive switching behavior^{4}. This RRAM device demonstrated exceptional switching endurance with over 5000 switching cycles and a high ON/OFF ratio of 150. Due to its robust resistive switching behavior and enhanced stability, these structures are wellsuited for applications in nonvolatile memory design, neuromorphic computing. Here,we have also prepared cross bar array to show how this metallohydrogel based RRAM device acts as in memory computing where computation and information storage are carried out at the same circuit level. Thus, by utilising crossbar arrays in memristorbased logic gate circuits, we can investigate various engineering approaches that rely on the concepts of inmemory computing. 

NN00.00027: MATERIALS PHYSICS


NN00.00028: Guestinduced phase transition leads to polarization enhancement in MHyPbCl_{3} Pradhi Srivastava, Sayan Maity, Varadharajan Srinivasan Hybrid perovskites offer more structural and chemical flexibility than traditional metal halide perovskites. In supertolerant 3D perovskites, a strong organicinorganic sublattice coupling can influence several physical properties significantly. Here, we use firstprinciples calculations to explore the structural and polar properties of one such member, methylhydrazinium lead chloride, MHyPbCl_{3}, as it transitions from highly polar PhaseI to less polar PhaseII upon cooling. From a host/guest perspective, the two phases vary structurally in the guest (MHy) orientation and the two differently distorted host (lead halide) layers. Unlike most hybrid perovskites, this transition is primarily driven by the guest reorientation, further confirmed by a minimum energy path calculation. Maximally localized Wannier functions identify the atomistic origin of polarization enhancement as the host atoms, especially the more distorted octahedral layer. The guest, despite being the primary order parameter for transition, has a negligible contribution, in contrast to prior suggestions. The host distortion also induces significant feedback polarization on the guest molecule, which alters the density of states occupied by the guest at the band edge, leading to a nontrivial impact of the guest on optoelectronic properties.


NN00.00029: MAGNETISM


NN00.00030: Investigation of magnetic ground state of double perovskite oxide Nd_{2}FeCrO_{6} using neutron diffraction and muon spin spectroscopy Saurav Kumar, Giuseppe Muscas, Francesco Congiu, Tapati Sarkar, Som Datta Kaushik, Hubertus Luetkens, Soumya J Ray The transitionmetal atoms at B and B’ sites in double perovskite oxide (DPs) having chemical formula A_{2}BB’O_{6} often lead to complex magnetic behaviour and act as a source of intriguing physics. The combined effect of spin, charge and orbital degree of freedom, such as the interaction between the spins at the B/B’ sites, Coulomb interaction, spinorbit coupling, crystal field effects, etc., give rise to exotic magnetic states. We used neutron diffraction and muon spin spectroscopy techniques [1] together with DC magnetometry and calorimetric measurements to elucidate the magnetic ground state and the origin of a lowtemperature anomaly in semiconducting DPs Nd_{2}FeCrO_{6}.Structural analysis using Xray and neutron diffraction techniques confirms the B siteordered monoclinic phase. While the temperaturedependent neutron diffraction measurement decerns the ferrimagnetic ground state with a net magnetic moment of ~2μB, arising due to antiferromagnetic interaction between Fe and Cr sublattice, muon spin spectroscopy asserts the existence of dynamic longrange commensurate magnetic order below the transition temperature 250 K . Thermal evolution of transverse and longitudinal muon spin relaxation rates reveals that the negative magnetization arises due to the ordering of Nd ion below 20K. Thus, complementary experimental techniques give insight into the microscopic magnetic properties of the system. 

NN00.00031: A FirstPrinciples Investigation of VClBr_{2}: A Novel van der Waals Ferromagnetic Semiconductor Subhasmita Kar, Puja Kumari, Neelam Gupta, Subham Sahoo, Soumya Jyoti Ray The discovery of longrange magnetic ordering in twodimensional (2D) materials has posed both challenges and opportunities, revealing novel physical phenomena. These materials, featuring spinpolarized electrons/holes and atomic layer thickness, underpin advanced information technology with high integration, ultrafast response, and low power consumption. Monolayer CrI_{3}, as a demonstrated member of this family [1], displays adjustable interlayer magnetic coupling, rendering it highly favorable for spintronic applications. Similarly, the centrosymmetric structure of Cr_{2}Ge_{3}Te_{6}, functioning as a ferromagnetic semiconductor [2], presents diverse opportunities for the creation of 2D magnetoelectric devices and magnetooptic applications. In this study, inspired by recent findings, we conducted a comprehensive investigation into the electronic and magnetic properties of monolayer VClBr_{2} [3] using firstprinciples density functional theory. This material represents a novel form of an intrinsic ferromagnet in the twodimensional realm, displaying semiconducting traits. Under strain ranging from 1% to 5%, it maintains consistent ferromagnetic (FM) characteristics. A shift to antiferromagnetic (AFM) phase occurs between 5% and 1% strain. When exposed to an electric field (E_{z} = 2.5 V/nm), VClBr_{2} displays FM ordering, transitioning to AFM when the field increases from E_{z} = 5 V/nm to 10 V/nm. 

NN00.00032: Twist controlled Spintransport across Phosphorene/Nickel (111) Spinterfaces Puja Kumari, Subhasmita Kar, Neelam Gupta, Shivani Rani, Soumya Jyoti Ray The electron's spin serves as a crucial information carrier in spintronic devices, which is extremely important for the growth of quantum computing applications, highdensity data storage, highfrequency devices, magnetoelectrics, etc. Phosphorene [4], a novel 2D semiconductor, offers significant potential for nanoelectronic, optoelectronic, and spintronic applications due to its inherent bandgap, high mobility, excellent spin diffusion and relaxation time [3], and ambipolar nature. In this study, we explored the transmission probability of spin carriers from a Ni electrode into phosphorene using first principlesbased density functional theory (DFT) in conjunction with the nonequilibrium Green’s function (NEGF) method. By increasing the number of phosphorene layers (N = 1, 2, 3) and incorporating a twist mechanism, we significantly enhanced the efficiency of spin injection from Ni to the phosphorene layer. We systematically examined the structural, electronic, and magnetic characteristics of the P/Ni(111) junction. On the Ni surface, the mono, bi, and trilayers of phosphorene exhibited metallic behavior. The electronic bands near the Fermi level varied with the twisted angles and observed ohmic contact between phosphorene and the Ni(111) surface. The majority carrier was spindown at the Fermi level, with an induced magnetic moment of 0.009 μ_{B} in phosphorene and an enhanced magnetic moment in the Ni atom. Moreover, the currentvoltage characteristics displayed negative differential resistance (NDR effects), with peaktovalley ratio (PVR) and sharpness factor (S_{E}) varying with the twisted angle. The efficiency of spin injection increased with the number of phosphorene layers, and twisting modified the spin injection efficiency, resulting in an increase of up to 60%. These findings offer valuable theoretical insights into the transmission of spin carriers within phosphorene layers on a magnetic substrate, suggesting a novel approach for designing spintronic devices utilizing phosphorene. 

NN00.00033: On Spin Glass and Its Magnetism Dynamics Premarun Barik Spin glasses are complex and disordered magnetic systems that have attracted considerable attention from physicists, mathematicians, and computer scientists over the past few decades. Despite extensive research, many unanswered questions remain about the nature of spin glass systems and their behavior under a magnetic field. Numerically simulating the magnetism dynamics of spin glass models will give us more insights about spin glass systems, rather than waiting for infinite time for the system to equilibrate. In our research we have used a 2D EdwardAnderson Ising spin glass system and on top of the system we have kept ferromagnetic blocks to create locally applied magnetic fields that affect the magnetism dynamics of spin glass local moments. Using numerical simulation employing the Kinetic Monte Carlo sampling method, which helps us sample the rarer events to overcome the longer relaxation time problem, we try to understand how the magnetism dynamics of spin glass is affected by the arrangement and intensity of the locally applied magnetic field. 

NN00.00034: COMPUTATIONAL PHYSICS


NN00.00035: Investigation of the SnSSe Janus monolayer as the solution for efficient thermoelectric materials Ameneh Bahadori, Zahra Shomali Nowadays, in order to increase the energy efficiency, the use of thermoelectric materials has been suggested as the solution. Thermoelectric materials can convert heat in to electricity. This transformation is described by the Seebeck effect. The ability of thermoelectric materials is measured by ZT parameter. 

NN00.00036: UVVis absorption spectra using semiempirical Hamiltonian plus a machine learning model Ezekiel Oyeniyi Machine learning (ML) is becoming a powerful tool for obtaining accurate properties of materials at a reduced computational cost. This work shows that semiempirical Hamiltonian, INDO/s + machine learning models (INDO/s+ML) could give highlevel first principle results. The machine learning models were used to add corrections to INDO/s absorption spectra to produce TDDFT absorption spectra. Excitation energy and oscillator strength corrections for 16k+ organic molecules were learned using the Kernel Ridge Regression (KRR) and Neural Network (NN) models. The INDO/s+ML predicts TDDFT excitation energies and oscillator strengths within MAE/RMSE of 0.15/0.23 eV and 0.04/0.11, respectively, for 3600 organic molecules not included in the training. The calculated spectra for these molecules with INDO/s+ML agree well with those from TDDFT. 

NN00.00037: Nonlocal heat transport in Silicon MOSFETs Roya Baratifarimani, Zahra Shomali abstract 

NN00.00038: Unsupervised detection of quantum phases and their local order parameters from projective measurements Kacper J Cybinski, James Enouen, Antoine Georges, Anna Dawid Recently, machine learning has become a powerful tool for detecting quantum phases. While the sole information about the presence of transition is valuable, the lack of interpretability and knowledge on the detected order parameter prevents this tool from becoming a customary element of a physicist's toolbox. Here, we report designing a special convolutional neural network with adaptive kernels, which allows for fully interpretable and unsupervised detection of local order parameters out of spin configurations measured in arbitrary bases. With the proposed architecture, we detect relevant and simplest order parameters for the onedimensional transversefield Ising model from any combination of projective measurements in the x, y, or z basis. Moreover, we successfully tackle the bilinearbiquadratic spin1 model with a nontrivial nematic order. We also consider extending the proposed approach to different lattice geometries and detecting topological order parameters. This work can lead to integrating ML methods with quantum simulators studying new exotic phases of matter. 

NN00.00039: QUANTUM INFORMATION


NN00.00040: Rydberg Parity Measurement Hadis Salasi, Mohammadsadegh Khazali The combination of atomlight interaction coupling and Rydberg interaction has revolutionized the field of quantum technology, leading to a wide range of applications [113]. One such application is the nondestructive parity measurement of collective qubit states in multiple atoms with applications on Quantum computation, simulation, and optimization. In this talk, we propose a robust and highfidelity scheme for constructing a nondestructive Rydberg parity meter. With this meter, we can determine the parity information of a bipartite state without destroying it, allowing us to utilize the output bipartite state for further quantum information processing tasks. Specifically, an auxiliary atom can sense the state of the plaquette spins and change its state only based on the parity of the central atom [1213]. We then measure the state of the auxiliary atom to reveal the parity of the plaquette. We also analyze the performance of the Nondestructive Rydberg Parity Meter (NRPM) under realistic experimental parameters and consider the impact of decoherence sources. 

NN00.00041: Highfidelity, multiqubit generalized measurements with dynamic circuits Petr Ivashkov, Derek S Wang, Gideon Uchehara, Alireza Seif, Liang Jiang Generalized measurements, also called positive operatorvalued measures (POVMs), can offer advantages over projective measurements in various quantum information tasks. Here, we realize a generalized measurement of one and two superconducting qubits with high fidelity and in a single experimental setting. To do so, we propose a hybrid method, the "Naimarkterminated binary tree," based on a hybridization of Naimark's dilation and binary tree techniques that leverages emerging hardware capabilities for midcircuit measurements and feedforward control. Furthermore, we showcase a highly effective use of approximate compiling to enhance POVM fidelity in noisy conditions. We argue that our hybrid method scales better toward larger system sizes than its constituent methods and demonstrate its advantage by performing detector tomography of symmetric, informationally complete POVM (SICPOVM). Detector fidelity is further improved through a composite error mitigation strategy that incorporates twirling and a newly devised conditional readout error mitigation. Looking forward, we expect improvements in approximate compilation and hardware noise for dynamic circuits to enable generalized measurements of larger multiqubit POVMs on superconducting qubits. 

NN00.00042: Extended Keldysh formalism for entropy evaluation Julian Rapp The Keldysh formalism is a key approach for calculating Green's functions out of equilibrium. We present a scheme to utilize the main part of the formalism, the closed time contour, for entropy production calculations in open quantum systems. To this end, we apply the formalism not to Green's functions, but to density matrices. By extending the Keldysh contour to multiple connected contours for copies of the density matrix, we use it to represent flows of Rényi entropies, and determine symmetries in perturbative calculations. This scheme is applied to simplify calculations of von Neumann entropy production. 

NN00.00043: Towards quantum control of an ultracoherent mechanical resonator with a fluxonium qubit Kyrylo Gerashchenko, Baldo Luis Najera Santos, Rémi Rousseau, Himanshu Patange, Angela Riva, Marius Villiers, Tristan Briant, Tristan Briant, PierreFrancois Cohadon, Antoine Heidmann, Helene Le Sueur, Alain Sarlette, Clarke Smith, Zaki Leghtas, Emmanuel Flurin, Emmanuel Flurin, Jose Palomo, Michael Rosticher, Thibaut Jacqmin, Samuel Deléglise Beyond their applications in quantum computing, superconducting qubits are a powerful platform to probe various quantum phenomena in the context of hybrid quantum systems [1]. However, most of them are confined to the GHz frequency domain, limiting the class of systems they can interact with. Building upon the heavy fluxonium architecture introduced by [2], we have developed a superconducting qubit with an unprecedentedly low transition frequency of 1.8 MHz [3]. Notably, we have demonstrated a qubit with a coherence time exceeding 30 μs, a sideband cooling scheme to prepare the qubit in a pure state with 97.7% fidelity, and singleshot readout capability. Moreover, by detecting a weak charge modulation by repeated qubit interrogation, we demonstrate the highsensitivity of this qubit architecture to a nearly resonant ACcharge drive, proving its potential in a hybrid circuit scenario. We will finally present our recent efforts to achieve the strong coupling regime between this qubit and an ultracoherent softlyclamped mechanical membrane. 

NN00.00044: SHOCK COMPRESSION OF CONDENSED MATTER


NN00.00045: High pressuretemperature superionic states of P3 brucite [Mg(OH)_{2}] promoting enhanced protonic conductivity Sudip Kumar Mondal, Pratik Kumar Das, Nibir Mandal


NN00.00046: Investigating the role of compression rates in pressure induced polymerization of crystalline acrylamide using abinitio molecular dynamics Rashid Rafeek V Valappil, Sayan Maity, Ashwini Anshu, Lavanya M. Ramaniah, Varadharajan Srinivasan Pressureinduced transformations in molecular crystals with varying pressure increase rates (PIRs) can enable the kinetic control of the obtained phase. Herein, we investigate the dependence of PIR on the pressureinduced polymerization of acrylamide. 0 K optimizations and room temperature molecular dynamics simulations at two different PIRs are used to characterize the structural evolutions and transformation mechanisms. Quasistatic compression at 0 K suggests polymerization to a 3dimensional polymer, whereas rapid compression indicates the existence of multiple metastable polymers with lower activation barriers for polymerization. Room temperature ab initio MD simulations led to different structural evolutions based on the applied PIR. Although both compression pathways eventually yield the same metastable polymer, rapid compression results in disordered polymers. The mechanism of formation as well as the structural and electronic properties of the various polymers obtained are characterized. Our results suggest a hierarchical route towards the thermodynamic polymer through other metastable polymers. 

NN00.00047: FLUID DYNAMICS


NN00.00048: Bulk nanobubble generation by gas supersaturation method. Aakriti Sharma For the past decade, nanobubbles have been shown to have numerous applications due to their unique properties. Despite its potential in enhancing gasliquid operations, limited to no studies have been conducted on nanobubble generation in pure organic solvents with strong scientific evidence . Furthermore, there is no direct evidence that explains the generation of nanobubbles by gas supersaturation mechanism. Since there is a strong dependence of gas solubility over temperature, therefore, a solvent at a high temperature, when, mixed with the same solvent at a low temperature releases the excess gas that may nucleate to form nanobubbles. The nanobubble generation was carried out with the variation in the temperature difference between hot and cold solvents ranging from 10°C to 80°C in the alcohols i.e., butanol, propanol, ethanol, methanol, and water. The nanobubbles are characterized by NTA (Nanoparticle Tracking Analysis) and DLS (Dynamic Light Scattering) in terms of bubble diameter, population and zeta potential. The results reported the formation of nanobubbles to be higher with maximum concentration in the range of <![if gte msEquation 12]> style='msobidifontstyle:normal'>7.78× style='fontsize:12.0pt;msoansifontsize:12.0pt;msobidifontsize:12.0pt; 

NN00.00049: ENERGY RESEARCH AND APPLICATIONS


NN00.00050: TwoDimensional Janus VSeTe monolayer with ultralow lattice thermal conductivity for Thermoelectric Application Neelam Gupta, Shivani Rani, Puja Kumari, Shubham Sahoo, Soumya Jyoti Ray Janus 2D materials have shown tremendous potential for thermoelectric applications [1]. In this work, we have calculated the electronic and thermoelectric properties of VSeTe monolayer with the help of Density functional theory and Boltzmann transport equation [2,3]. The electronic band structure revealed the semiconducting nature of VSeTe, with an indirect band gap of 0.28eV. The phonon dispersion curve established the dynamic stability of the proposed structure. Morever, to confirm the thermal stability of the system, Ab initio molecular dynamics (AIMD) simulations were performed at 300K. We have also calculated the elastic constant to check the mechanical stability of the structure. The thermoelectric parameters such as Seebeck coefficient, power factor, and electrical conductivity have been calculated under constant relaxation time approximation at temperatures of 300K, 600K, and 800K. The lattice thermal conductivity (K_{l }) at room temperature has been found to be very low in VSeTe monolayer as compared to other Janus monolayers [1]. An ultralow value of K_{l }of 0.19 W/mK at room temperature was observed in the Janus monolayer VSeTe, primarily due to very low group velocity and short phonon lifetime in VSeTe. This ultralow lattice thermal conductivity and high power factor, result in a high thermoelectric figure of merit close to the value of 1 at room temperature. Our finding indicates the potential application of VSeTe monolayer for thermoelectric devices in energy harvesting at room temperature. 

NN00.00051: Poster: Boosting thermoelectric efficiency via cationic sites in spinel oxides Ashutosh Srivastava, Madhubanti Mukherjee, Abhishek K Singh Decoupling electronic and thermal transport properties remains the biggest challenge in finding efficient thermoelectric materials. We demonstrate an approach to decoupling the complex interdependence among electrical conductivity, Seebeck coefficient, and lattice thermal conductivity in spinel oxides. Utilizing the effects of tetrahedral and octahedral coordination on bonding characteristics, we demonstrate tuning the electronic and thermal transport properties of cobaltbased spinel oxides ACo_{2}O_{4}. Tetrahedrally coordinated cation A (Zn/Cd) controls the electronic transport, while thermal transport has been controlled by octahedrally coordinated cation B (Co). The combination of heavy bands and contribution of the tetrahedrally coordinated environment of Co near valence band maxima (VBM) and conduction band minima (CBM) results in an enhanced power factor. Additionally, the substitution of Cd for Zn on an octahedrally coordinated cation site leads to one order of magnitude reduction in the lattice thermal conductivity. This reduction is attributed to the significant mass difference, phonon modes, phonon lifetime, and remarkably strong anharmonic scattering introduced by Cd. Simultaneously achieved high power factor and low lattice thermal conductivity resulting in an enhanced figure of merit value of 1.68 for Cdspinel. The approach of decoupling atomic contributions utilizing various cationic sites demonstrates a potential route to enhance thermoelectric performance. 

NN00.00052: A Photorechargeable Supercapacitor using CsPbBr_{3}Activated Carbon Composite PRIYANKA ASHIWAL, PRASHANT TRIPATHI, KEDAR SINGH The need for renewable and sustainable energy resources is increasing exponentially. Due to their high specific power, capacitance, and cyclic stability Supercapacitors (SC) emerge a promising alternative for renewable energy storage device and have drawn tremendous attention over the past decade. Hybrid halide perovskite materials, exhibiting mixed electronicionic conductivity and outstanding optical properties, hold great promise as potential candidates for advancing this field. In the current study, CsPbBr_{3} nanoparticles were synthesized using the hot injection method under a nitrogen gas environment, and their potential for Photorechargeable Supercapacitor applications was explored. To enhance the energy and power density of the CsPbBr_{3} supercapacitors, composites of CsPbBr_{3} and Activated carbon (AC) were fabricated. The AC was prepared through the solvothermal method, followed by activation using KOH at 750 ºC in an argon atmosphere. The CsPbBr_{3}AC composites were synthesized by introducing the desired amount of AC (powder) into a threeneck flask containing all the necessary precursors, using the similar reaction conditions used for the synthesis of pristine CsPbBr_{3}. Detailed structural and spectroscopic characterizations were performed, confirming the formation of CsPbBr_{3}AC composites. Supercapacitors were realized using CsPbBr_{3}AC composites as the working electrode, Platinum as the counter electrode, and Ag/AgCl as the reference electrode. Electrochemical measurements were carried out using cyclic voltammetry (CV) and galvanostatic charging/discharging (GCD) under both dark and illuminated conditions. These devices exhibited high capacitance and excellent capacitive retention, demonstrating their significance in Photorechargeable Supercapacitor applications. 

NN00.00053: Excellent Supercapacitive Response of Microwavesynthesized TwoDimensional Transitional Metal Oxide Using Metal Chloride Precursor Towhidur Rahaman, Soumya J Ray


NN00.00054: Epitaxial nanostructure derived robust energy storage performance in symmetric and asymmetric ultracapacitors Monika Sharma Epitaxial nanostructure derived robust energy storage performance in symmetric and asymmetric ultracapacitors 

NN00.00055: INDUSTRIAL AND APPLIED PHYSICS


NN00.00056: Super Moiré of Controlled Stacked Monolayers Chun An Chen, PoYen Liu, ChungJen Chen, GuanYi Wu, Shangfan Lee, ChiaSeng Chang, LihJuann Chen, YiHsien Lee Moiré lattices have recently emerged as a highly promising platform for the exploration of quantum states and correlated physics.[1,2] The introduction of periodic Moiré potential within superlattices has the profound effect of modifying their electronic band structures, giving rise to novel quantum phenomena, notably Moiré excitons and Moiré phonons. In this study, a deeper Moiré potential is realized by controlled stacking of monolayers of transition metal dichalcogenides (TMDs) via chemical vapor deposition (CVD). 

NN00.00057: Comparative study of mechanical, electronic, and optoelectronic properties of all inorganic CsPbX_{3 }(X = Cl, Br, I) perovskite by DFT approach Esrat Jahan, Md. Rafiqul Islam, Md. Mehedi Hassan Mitul The organic and inorganic hybrid Pbhalide perovskites with formula ABX_{3} (A is a monovalent organic cation, B is a lead cation and X is a halide anion) have emerged as a revolutionary semiconductor in various applications. But the longterm stability and Pb toxicity of these perovskites attract more and more attention, therefore, all inorganic perovskites became an alternative perovskite for optoelectronic applications. To this point of view, in this research work, we theoretically study the mechanical, electronic and optoelectronic properties of CsPbX_{3} (X = Cl, Br, I) perovskites for potential optoelectronic and solar cell applications. The first principles calculations were performed based on the density functional theory (DFT) in the framework of generalized gradient approximation (GGA) in CASTEP code software. The electronic properties calculation shows that CsPbI_{3}, CsPbBr_{3} and CsPbCl_{3} direct band gap nature with the band gap lying between 1.47 eV and 2.20 eV. The lattice parameters and volume strongly depend on the halide components. The mechanical stability is higher for Clbased halides than the rest halides. It is also seen that the optical properties such as reflectivity, dielectric constants, refractive index, optical conductivity and absorption coefficient can be tuned by varying the halide component which may pave the way to develop optoelectronic and advanced electronic devices. 

NN00.00058: Synthesis and study of Manganese(Mn) doped Molybdenite(MoS_{2}) wafer shape sample by using spark plasma Sintering technique in conjunction with master curve analysis Parnian Dehghani Molybdenite(MoS_{2}) as a mineral with semiconducting characteristics might be an intriguing substitute for silicon within (opto)electronic industry in future. In bulk, it is indirect gap semiconductor(Eg=1.3 eV) with high dielectric constant. We have made wafer shape Manganese(Mn) doped (14%) Molybdenite by using spark plasma Sintering at high vacuum reaching high temperature (T~2200 K). The wafer has 1 inch diameter and 1•5 mm thickness with gray color. The temperature and pressure profile implemented during Sintering process were in such a manner to keep polycrystalline nature of the processed powder (through master curve analysis) confirmed by PXRD analysis. Optical study of sample proved semiconducting properties of sample with Eg=1.28 eV. Temperature study of magnetic succeptibility have shown para to ferromagnetic phase transition at curie temperature of 240K. In all, bulk magnetically doped Molybdenite sample with relevant semiconducting properties have been made through Sintering technique and studied through structural, optical and magnetic characterization techniques with promising results. We plan to present our findings at aps march meeting. 

NN00.00059: An Investigation of Structural and IV characteristics of (1x)LaMnO3.(x)rGO Nanocomposite Samples Karuna Kumari, Subhasmita Kar, Soumya Jyoti Ray The study focused on (1x)LaMnO3 (LSMO).(x)rGO nanocomposites, exploring their structure and electrical behavior. Using XRD, FESEM, and Raman spectroscopy, dual phases were observed. Distinctive bipolar resistive switching behavior in IV profiles indicated potential electronic applications. Increasing rGO led to an oxygendeficient region, confirmed by XPS. Oxygen vacancies and ions were identified as pivotal in resistive switching. Sample x = 0.001 exhibited superior characteristics. HRTEM validated distinct lattice spacings. Conduction primarily followed Ohmic and Schottky emission phenomena. The research offers insights for engineering nanocomposites in electronics. 

NN00.00060: A comparative analysis of frequencydoubling in typeII quasiphasematched KTP crystals SK W AHAMED, Nilesh Tiwari, Om Shankar, Joyee Ghosh Second harmonic generation (SHG) is a widely used nonlinear threewave mixing process to characterize different bulk nonlinear crystals/waveguides e.g., beta barium borate (BBO), potassium titanyl phosphate (KTP), Lithium niobate (LN), etc. for its implementation in nonclassical experiments utilizing spontaneous parametric downconversion (SPDC) for the generation of entangledphoton pair sources. Such sources are useful candidates for applications in Optical Quantum technology e.g., quantum key distribution (QKD) and quantum computing. As a characterization tool for the SPDC source, we experimentally investigated the variation of second harmonic (SH) power by tuning the crystal temperature for three (10mm, 20mm, and 30mm) periodically poled KTP (ppKTP) crystals, phasematched for the typeII process (H+V→H). We observed an increment in the conversion efficiency of SHG from 2.96 to 12.6 (P_{SH}/P_{pump}*10^{6}) and a decrement in the temperature bandwidth from 2.80°C to 1.50°C with an increase in crystal length, respectively, validated by our theoretical calculations. Moreover, the focusing of the pump beam reveals the emergence of asymmetry in the SH power for different crystal lengths due to a competition between the confocal parameter attaining the crystal length, indicating the need for an optimization of the focusing parameters. Such thorough optimization of different parameters e.g., pump focusing, and crystal temperature is crucial for its utilization in different quantum applications. 

NN00.00061: DATA SCIENCE


NN00.00062: Simmulated Annealing for Global Search Rohit Goswami, Ruhila S., Amrita Goswami, Sonaly Goswami, Debabrata Goswami Global search over black box functions describes much of computational physics, typically for determining critical points on energy surfaces. As surrogate (machine learned) models have come of age and taken center stage, global search of optimal parameters (or "hyper parameters") for these models have become concomitantly more important. For most systems (including neural networks) finding optimal hyper parameters is far from easy. Most implementations focus on using first order search methods (e.g. batch stochastic gradient methods). We demonstrate the applicability of simulated annealing (via a new, high performance anneal python package) to the problem of finding minima in both hyper parameter surfaces and standard energy systems. Our approach is unique in that it demonstrates the coupling (at a computational implementation level) of the related concept of Metropolis Hasting sampling and its connections to simulated annealing. We will introduce several standard paradigms and demonstrate how these can be "lifted" into a unified framework using objectoriented programming in Python. We demonstrate how clean, inter operable, reproducible programming libraries can be used to access and rapidly iterate on variants of Simulated Annealing in a manner which can be extended to serve as a best practices blueprint or design pattern for a datadriven optimization library. 

NN00.00063: Evaluating YOLO Object Detection Models Under Adverse Lighting Conditions Md Shah Imran Shovon, Md Ragib Shaharear, Jannatul Mowa Arzu This research looks at the problems that You Only Look Once (YOLO) object recognition models have when they have to work in adverse lighting. Even though YOLO models are generally very good at finding items, they have shown that they are not very good at identifying things when the lighting is bright or changes. Most of the study that has been done so far has focused on finding the best conditions for object detection algorithms, which has left a major knowledge gap. In order to fill this gap, the main goal of this study is to carefully look at how well YOLO models work when lighting conditions aren't ideal. It is very important to understand these limits because they have big effects on realworld situations, like how safe selfdriving cars are when the lighting changes and how well security systems work. The main objective of the study is to make object detection algorithms like YOLO more reliable and robust in a wide range of environmental situations. 

NN00.00064: Training Convolutional Neural Networks with the ForwardForward algorithm Riccardo Scodellaro, Ajinkya Kulkarni, Frauke Alves, Matthias Schroeter The recent successes in analyzing images with deep neural networks are almost exclusively achieved with Convolutional Neural Networks (CNNs). The training of these CNNs, and in fact of all deep neural network architectures, uses the backpropagation algorithm where the output of the network is compared with the desired result and the difference is then used to move the weights of the network towards the desired outcome. In a 2022 preprint, Geoffrey Hinton suggested an alternative way of training which passes the desired results together with the images at the input of the network. This so called Forward Forward (FF) algorithm has up to now only been used in fully connected networks. In this paper, we show how the FF paradigm can be extended to CNNs. Our FFtrained CNN achieves a classification accuracy of 99.0% on the MNIST handwritten digits dataset. We show how different hyperparameters affect the performance of the proposed algorithm and compare the results with the standard backpropagation approach. Furthermore, we use Class Activation Maps to investigate which type of features are learnt by the FF algorithm. 

NN00.00065: LASER SCIENCE


NN00.00066: Flexural modes at the photon sphere of a black hole Jiaoqing Wang, Chenni Xu, Aswathy Sundaresan, Patrick Sebbah The spacetime curvature in the vicinity of massive black holes induces the bending of ray trajectories and the trapping of light in a specific region of space called the photon sphere. We mimic in the laboratory the behavior of waves near a black hole by investigating the modes of vibration on a 3D curved surface corresponding to a particular metric of the black hole. This surface can be transformed to a flat disk with nonuniform distribution of refractive index. Here, we consider elastic waves guided in a thin plate with nonuniform thickness, which corresponds to a varying velocity. Selective laser melting has been used to 3Dprint our model with an aluminum alloy. A short pulse is propagated, and the spatiotemporal profile of the velocityfield is recorded by scanning a laser vibrometer. The quasimodes of the system are obtained by modal analysis in the Fourier domain. We find two different classes of modes: (1) Modes similar to the eigensolutions of a uniform disk, including whispering gallery modes; (2) Modes strongly confined within the plate, along a circle with radius corresponding to the photon sphere. Interestingly, this radius is frequency dependent, which is supported by our theory in the regime of wave optics. These observations are supported by full 3D numerical simulations. This work reveals a new type of highQ modes scared on the stable or unstable orbits, which offers interesting perspective for laser design, inspired from celestial objects. 

NN00.00067: PHYSICS OF CLIMATE


NN00.00068: Climate network analysis of extreme events: Tropical Cyclones Neelima M Gupte, Rupali Sonone We construct climate networks based on surface air temperature data to identify distinct signatures of tropical cyclones in the region of the Indian Ocean, which have serious economic and ecological consequences. The climate network shows a discontinuous phase transition in the size of the normalised largest cluster and the susceptibility during cyclonic events. We analyze these quantities for a year (2016) which had three successive cyclones, viz. Cyclone Kyant, cyclone Nada and cyclone Vardah, and compare these with a year (2017) where a single cyclone, cyclone Okhi was seen. The microtransitions in these two cases show distinct patterns. The signatures of the cyclones can be seen in other quantities like the degree distributions and other network characterizers. The distribution of teleconnections show a distinct behaviour in the cyclonic periods. Similarly, the distribution of nodes of high degree shows distinct behaviour in cyclonic and recyclonic periods. These three cyclones were seen in the Bay of Bengal. We also compare these with a cyclone, cyclone Ashoba (2015), seen in the Arabian sea where cyclones are rarer. We discuss the implications of these results for further analysis. 

NN00.00069: GENERAL PHYSICS


NN00.00070: Discovering the True Nature of Forces and Energies (The Unity of All of Them) Gh. Saleh There are four fundamental forces that are shaping the universe that we live in it. In this paper we are going to show that the basis of them are photon. 
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