Bulletin of the American Physical Society
APS March Meeting 2021
Volume 66, Number 1
Monday–Friday, March 15–19, 2021; Virtual; Time Zone: Central Daylight Time, USA
Session R55: Nanostructures and Metamaterials ILive
|
Hide Abstracts |
Sponsoring Units: DMP |
Thursday, March 18, 2021 8:00AM - 8:36AM Live |
R55.00001: Topological structures of and for light Invited Speaker: Kobus Kuipers The nominee was an invited speaker for the 2020 March meeting but had their talk canceled. I am resubmitting the nomination so it can be considered for the 2021 meeting. Their 2020 abstract is below: |
Thursday, March 18, 2021 8:36AM - 8:48AM Live |
R55.00002: Topological phases of electromagnetic waves in superlattices of negative- and positive- epsilon materials Akihiro Okamoto, Yosuke Nakata, Shuichi Murakami Recently, a new topological invariant is proposed to classify electromagnetic waves in an isotropic medium with positive or negative permittivity and permeability, and various interface modes such as surface plasmons are interpreted as topological boundary modes [1]. We expect similar topological phases of electromagnetic waves even for metamaterials. |
Thursday, March 18, 2021 8:48AM - 9:00AM Live |
R55.00003: Flat bands in magic-angle vibrating plates María Rosendo, Fernando Peñaranda, Johan Christensen, Pablo San-Jose Twisted bilayer graphene develop quasi-flat bands at specific ``magic'' interlayer rotation angles through an unconventional mechanism connected to carrier chirality. Quasi-flat bands are responsible for a wealth of exotic, correlated-electron phases in the system. In this work we propose a mechanical analogue of twisted bilayer graphene made of two vibrating plates, patterned with a honeycomb mesh of masses, and coupled across a continuum elastic medium. We show that flexural waves in the device exhibit vanishing group velocity and quasi-flat bands at magic angles, in close correspondence with electrons in graphene models. The strong similarities of spectral structure and spatial eigenmodes in the two systems demonstrate the chiral nature of the mechanical flat bands. We derive analytical expressions that quantitatively connect the mechanical and electronic models, which allow us to predict the parameters required for an experimental realization of our proposal. |
Thursday, March 18, 2021 9:00AM - 9:12AM Live |
R55.00004: Spatially shaping waves deep inside a forbidden gap Ravitej Uppu, Manashee Adhikary, Cornelis A. M. Harteveld, Willem L Vos Wave propagation inside crystals can be controlled through bandgap formation and engineering of resonant and functional features within (e.g. cavities). However, the Bragg interference of waves exponentially attenuates the waves from penetrating deep into the crystal, thereby disallowing access to these functional features and reducing the accessible functional volume of the crystal. Breaking this convention, here we demonstrate the ability to send waves much deeper into crystals. We study light in exemplary two-dimensional silicon photonic crystals. By spatially shaping the optical wavefronts, the intensity of laterally scattered light, that probes the internal energy density, is observed to enhance at a tunable depth within the crystal. We measured intensity enhancement factors of >100x and wave penetration to >8x the Bragg length. Our novel steering of waves inside a forbidden gap exploits the transport channels induced by unavoidable deviations from perfect periodicity, here unavoidable fabrication deviations. Importantly, the reconfigurability of the wavefronts enables programmable wave control, which was hitherto impossible, thereby opening up new avenues, for e.g. reconfigurable resonant photonic circuits in 3D photonic crystals. |
Thursday, March 18, 2021 9:12AM - 9:24AM Live |
R55.00005: The role of the electrostatic interlayer interaction in SiC/GeC heterostructures Kazi Jannatul Tasnim, Safia Abdullah R Alharbi, Md Rajib khan Musa, Simon Hosch Lovell, Zachary Alexander Akridge, Ming Yu 2D SiC and GeC sheets are polar materials with in-plane charge transfer from Si (Ge) to C atoms, and the electrostatic forces play a key role in intra-layer bonding. An interesting question is how the electrostatic interaction between layers, triggered by such charge transfer, plays a role in stabilizing the vertical heterostructures beyond vdW interaction? In this preliminary study, we have investigated the structural stability of 2D SiC/GeC bilayer heterostructure with different stacking and out-of-plane species ordering within the framework of density functional theory. We found that the electrostatic interlayer interaction leads a strong orbital hybridization between layers for the Si-C species ordering systems but a weak orbital hybridization between layers for C-C species ordering systems. Such species ordering dependent feature is also found in stabilizing interlayer distance. The electrostatic forces mainly stabilized the interlayer distance in Si-C ordering and the vdW interaction only make the system attain a lower cohesive energy. vdW interaction, on the other hand, mainly controls the interlayer distance and hybridization in C-C and Si-Ge orderings. Study of the electrostatic effects on the electronic and mechanical properties is undergoing. |
Thursday, March 18, 2021 9:24AM - 9:36AM Live |
R55.00006: Fundamental Limits to Performance of Photonic Nanostructures via Hierarchical Mean-Field Constraints: Upper Bounds on Scattering, Absorption, and Purcell Enhancement Pengning Chao, Sean Molesky, Weiliang Jin, Alejandro Rodriguez We present a general method for computing fundamental limits on photonic design objectives that apply to arbitrary structures dependent only on the material the structure is made of and its maximum footprint. From an algebraic analysis of the scattering properties of Maxwell’s equations, we introduce spatially localized constraints on the polarization field that can be organized as a hierarchy of resolutions, reminiscent of mean-field theories and multigrid/multi-scale methods. These constraints are leveraged via Lagrangian duality to produce upper bounds on far-field scattering/absorption cross-sections and near-field radiative enhancement, relevant to applications in single-photon extraction, photovoltaics, LED design, and Raman scattering. Far field bounds exhibit a transition from volume scaling in the quasistatic limit to area scaling in the geometric optics limit. Near field bounds show a transition from non-resonant to resonant enhancement with increasing device footprint and elucidate the limiting role of both material and radiative loss on the Purcell factor. Topology optimization results are presented, which in many cases approach within an order of magnitude of the bounds. |
Thursday, March 18, 2021 9:36AM - 9:48AM Live |
R55.00007: Hyperbolic phonon polaritons in calcite for nanoscale infrared confinement Vanessa Breslin, Daniel Ratchford, Alexander Giles, Adam Dunkelberger, Jeffrey C Owrutsky Phonon polaritons are collective oscillations resulting from the coupling of photons with optical phonons in polar materials and are supported within a material-specific spectral region called the reststrahlen band. In this region, the material behaves optically like a metal; it is highly reflective and has a negative real part of the permittivity. When polar materials are nanostructured, phonon polaritons can enable a variety of near-field optical effects such as sub-diffraction light confinement. A polar material which supports phonon polaritons can also have anisotropic optical properties, such that different components of its permittivity tensor have opposite signs. These materials are referred to as hyperbolic as they behave optically like a dielectric and a metal along different crystal axes. Here, we report on the first observation of hyperbolic phonon polaritons (HPs) in calcite nanopillar arrays, demonstrate the aspect ratio dependence of the HP resonance frequencies, discuss fabrication challenges, and compare our results to numerical simulations and analytical models. The results of this work are an important first step towards creating a library of materials with the appropriate phonon properties to extend phonon polariton applications throughout the infrared. |
Thursday, March 18, 2021 9:48AM - 10:24AM Live |
R55.00008: Optically tunable topological photonic structures Invited Speaker: Natalia Litchinitser The nominee was an invited speaker for the 2020 March meeting but had their talk canceled. I am resubmitting the nomination so it can be considered for the 2021 meeting. Their 2020 abstract is below: |
Thursday, March 18, 2021 10:24AM - 10:36AM Live |
R55.00009: Tri- and Tetrahyperbolic Anisotropic and Bianisotropic Optical Metamaterials Maxim Durach Hyperbolic metamaterials have open iso-frequency Fresnel surfaces in momentum space and allow high-k electromagnetic waves. Recently, magnetic hyperbolic metamaterials were experimentally demonstrated [1] and bi-hyperbolic metamaterials were predicted [2]. In this work we introduce a complete taxonomy of optical metamaterials and show that all optical materials belong to one of the following topological classes: tetra-, tri-, bi-, mono- or non-hyperbolic, which includes 2 novel classes - the tetra- and trihyperbolic metamaterials [3]. The prefix in the name of each topological class indicates the number of the double cones in the high-k limit. We explain the formation of tri- and tetrahyperbolic phases in both anisotropic and bianistropic media with or without magnetoelectric coupling by hybridization of plasmonic and magnetic high-k Bloch waves [4]. We predict that tri- and tetrahyperbolic phases can appear in realistic metamaterial structures and will find applications in nanoresolution optics, emission rate and directivity control, and to achieve optical magnetism. |
Thursday, March 18, 2021 10:36AM - 10:48AM On Demand |
R55.00010: Type-III nodal loops and topological phase transition at metasurfaces. Haitao Li, Bo Hou, Chaundeng Hu Topological characteristics of Bloch energy bands have attracted a lot of attention in electronic systems as well as photonic systems. As an unique degeneracy configuration, nodal loop (NL)[1] is regarded as a twofold band degeneracy and forms a closed rings in the Brillouin zone. This kind of band structure has been studied in various periodic systems, but not yet been reported to realize in 2D microwave metasurfaces. Here, we experimentally demonstrate a NL degeneracy at a metasurface with bilayer subwavelength fractal pattern. Protected by mirror symmetry (MS) at z-direction, NL is realized in the metasurface and appears as a ring-like degeneracy between a nearly-flat band and a positive band. In addition, we experimentally show that the NL can transform into two Type-II Dirac points[2] along the Gama-X direction when Ms at z-direction is broken. After further symmetry breaking in fractal pattern, the DPs are gapped and the emergence of topological edge states is observed in the domain wall composed of the gapped metasurfaces. |
Thursday, March 18, 2021 10:48AM - 11:00AM On Demand |
R55.00011: Observation of bound photonic drumhead surface state in the radiation continuum Yu Wang, Xiaoxi Zhou, Bo Hou Nodal chain (NC) semi-metal forms a degeneracy ring in momentum space. With the projection of NC in the boundary, there is a special surface dispersion appearing at the crystal surface and termed drumhead surface state (DSS). Previously, experimental investigation on photonic NC and DSS has been made with metallic photonic crystals at microwave frequencies. However, the far-field detection of DSS and its coupling with the radiative mode have not addressed. Here, we studied the DSS through far-field angle-resolved reflection measurement and simulation, and found the bound property in the radiation continuum of the DSS center at Γ point in surface Brilliouin zone. Based on the temporal coupled-mode theory, we numerically obtain the radiative quality factor (Qr) of the DSS from reflection spectrum. Qr in Γ point tends to infinity for the DSS, leading to a bound state in the continuum (BIC). Our work establishes a connection between BIC and photonic topological surface state. |
Follow Us |
Engage
Become an APS Member |
My APS
Renew Membership |
Information for |
About APSThe American Physical Society (APS) is a non-profit membership organization working to advance the knowledge of physics. |
© 2024 American Physical Society
| All rights reserved | Terms of Use
| Contact Us
Headquarters
1 Physics Ellipse, College Park, MD 20740-3844
(301) 209-3200
Editorial Office
100 Motor Pkwy, Suite 110, Hauppauge, NY 11788
(631) 591-4000
Office of Public Affairs
529 14th St NW, Suite 1050, Washington, D.C. 20045-2001
(202) 662-8700