Bulletin of the American Physical Society
89th Annual Meeting of the Southeastern Section of the APS
Volume 67, Number 18
Thursday–Saturday, November 3–5, 2022; University of Mississippi, University, MS
Session H04: Device and Materials Characterization |
Hide Abstracts |
Chair: Gregory Vieira, Rhodes College Room: University of Mississippi Ballroom D |
Friday, November 4, 2022 8:30AM - 9:00AM |
H04.00001: Studying ultrafast carrier dynamics in GaAs and GaAs/AlGaAs devices with few-cycle pump-probe reflectometry Invited Speaker: Lingze Duan Over the last decade, advances in novel materials such as two-dimensional (2D) materials, metamaterials, plasmonics, and negative-electron-affinity (NEA) structures have triggered rapid growth in the development of ultrafast optoelectronic devices. This calls for simple yet effective approaches to characterize ultrafast dynamics in these materials and devices. Few-cycle pump-probe reflectometry (PPR) offers both high temporal resolution and broad spectral coverage in a simple configuration. In this talk, I will present our latest work on the study of transient carrier dynamics in bulk GaAs and photoelectron transportation/relaxation in GaAs/AlGaAs NEA photocathodes using few-cycle PPR. In addition to experimental results, theoretical models on photoelectron transportation in layered structures are also discussed, and theory-experiment comparisons are presented. |
Friday, November 4, 2022 9:00AM - 9:30AM |
H04.00002: Insulator-to-Metal Phase Transition in a Few-Layered 2D Semiconductor Field Effect Transistor Invited Speaker: Nihar R Pradhan Metal-to-insulator phase transition (MIT) in low dimensional materials and particularly two-dimensional layered semiconductors is exciting to explore due to the fact that it challenges the |
Friday, November 4, 2022 9:30AM - 9:42AM |
H04.00003: Fabrication of High Proportion of WS2 Monolayers Using Liquid Phase Exfoliation Method Arjun Dahal Due to their unique properties, tungsten disulfide (WS2) nanosheets, preferably monolayers, are promising materials for sensing, optoelectronic, catalysis, and energy storage applications. A simple, reliable, and cost-effective synthesis method is desirable to realize their applications. The liquid phase exfoliation method, which involves the mechanical exfoliation of layered materials in a solvent, has proven to be a promising technique for synthesizing nanosheets with high yields. In this study, we systematically examine the optimization of the fabrication of WS2 nanosheets by exfoliating the WS2 powder in isopropyl alcohol, a low boiling point solvent, using a low-power probe sonicator. The investigation of the atomic force microscopy images reveals that the exfoliated nanosheets comprise a significant proportion of monolayers and bilayers. Our study finds that the proportion of monolayers and bilayers can be elevated by more than 20% if the dispersions are centrifuged at higher speeds. Moreover, we show that prolonged sonication increases the proportion of monolayers, such as 11% more monolayers can be fabricated with a five-fold increase in sonication time. |
Friday, November 4, 2022 9:42AM - 9:54AM |
H04.00004: Effect of the amount of tungsten on the superconducting properties of Ni-W substrates based coated conductors. Anota Ijaduola, C L H Thieme, M W Rupich, A Goyal One of the main challenges in the use of high temperature superconducting wires, the YBa2Cu3O7-δ (YBCO) coated conductors (CC) in electric power applications is the amount of dissipation or loss. Ni-W alloys are used as substrates for rolling assisted biaxially textured substrate (RABiTS) tapes because of their comparably low loss and ease of manufacturing. In this work, we have determined the amount of ferromagnetic loss in a series of biaxially textured Ni1-xWx materials with compositions x = 5 and 9 at.% W. We also measured the critical current density Jc in two different samples of coated conductor; one fabricated with the Ni-5at.%W substrate and the other with the Ni-9at.%W substrate. The aim is to determine if the type of substrate used will influence the amount and the property of Jc measured. While the Ni-5at.%W shows a higher ferromagnetism (and loss), the Jc measured in both CC is fairly similar. The field and temperature dependence of the Jc in the two samples is also analyzed. |
Friday, November 4, 2022 9:54AM - 10:06AM |
H04.00005: Nonreciprocal electric current in a bulk Rashba semiconductor Aniruddha Pan, D. C Marinescu We calculate the nonreciprocal charge current in a bulk semiconductor with Rashba spin-orbit coupling subjected to crossed electric and magnetic fields. By using a second-order distribution function derived in a perturbative approach that considers the change in the local electron energy induced by the electric field [Physical Review B, 99(24), 245204], we find that, in contrast with previous theoretical estimates, a charge current proportional to the applied magnetic field exists for all values of the chemical potential, above or below the band crossing point (BCP), the energy where the two chiral conduction bands intersect. The persistence of the quadratic electric current across the BCP is a consequence of the chiral dependence of the relaxation times, an effect neglected before. |
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