Bulletin of the American Physical Society
Mid-Atlantic Section Meeting 2021
Volume 66, Number 18
Friday–Sunday, December 3–5, 2021; Rutgers University, New Brunswick, New Jersey
Session C01: Quantum Matter: Correlated |
Hide Abstracts |
Chair: David Vanderbilt, Rutgers University Room: 201A |
Saturday, December 4, 2021 9:00AM - 9:36AM |
C01.00001: Understanding correlated and disordered materials using quantum cluster theories. Invited Speaker: Hanna Terletska Numerical analysis has become a powerful tool for studying strongly correlated systems with electron-electron interactions and disorder. Electron localization (driven by electron interactions or disorder) is the key phenomenon featured in many quantum materials. Various complex phases of matter find their roots near such electron localized states. Hence, its understanding and numerical modeling is critical for the further control and application of quantum systems. Quantum cluster theories, such as the dynamical cluster approximation, have emerged as powerful numerical tools for describing the many-body correlation effects near the electron localized states. In this talk, I will show how the cluster extension of the DMFT can be used to successfully describe the electron localization near the Mott and charge order phase transitions in two-dimensional Hubbard model and beyond. I will also present the recent results on the electron localization in disordered systems using the typical medium quantum cluster approach. I will demonstrate how it can be used to describe the Anderson localized states in models and materials. [Preview Abstract] |
Saturday, December 4, 2021 9:36AM - 9:48AM |
C01.00002: Building a beyond-DFT database of spectral functions for correlated materials Subhasish Mandal, Kristjan Haule, Karin Rabe, David Vanderbilt Generating databases of the electronic structure of materials is a key to data-science-driven materials discovery. Many existing materials databases, which were constructed in the spirit of the Materials Genome Initiative, rely almost exclusively upon DFT engines and often make incorrect predictions for many correlated materials. Because qualitative predictions of excited-state properties usually require beyond-DFT methods, various advance methods such as meta-GGAs, hybrid functionals, GW, and dynamical mean-field theory (DMFT) have been developed to describe the electronic structure of correlated materials. However, the expected accuracy of these methods when applied to various classes of materials remains unclear. It is thus of pressing interest to compare their accuracy for different types of materials, and at the same time, to build a broad publicly-available database of the results of beyond-DFT calculations[1]. In this talk, I will discuss some of the challenges involved in generating such a beyond-DFT database, and show how we have overcome these challenges in our systematic study of these methods on various training sets of moderately and strongly correlated materials. [1]https://jarvis.nist.gov/jarvisbdft/;Mandal et al. npj. Comput. Mater. 5, 115 (2019); arXiv:2101.03262 [Preview Abstract] |
Saturday, December 4, 2021 9:48AM - 10:24AM |
C01.00003: Nanotextured dynamics of a light-induced phase transition in VO2 Invited Speaker: Aaron Sternbach Programming properties of quantum materials at will is a central goal of modern condensed matter physics. Light stands out as a particularly powerful tool for inducing properties on-demand [1]. Light-induced states, however, can exhibit complex phase separation at the nanoscale. In this talk I will discuss our inquiry into transient nanotextured heterogeneity in vanadium dioxide (VO2) thin films during a light-induced insulator-to-metal transition (IMT) [2]. Room temperature, steady-state, phonon enhanced nano-optical contrast reveals preexisting ``hidden'' disorder in VO2. ~The observed contrast is associated with inequivalent twin domain structures. Upon thermal or optical initiation of the IMT coexisting metallic and insulating regions are observed. Correlations between the transient and steady-state nano-optical textures reveal that heterogeneous nucleation is partially anchored to twin domain interfaces and grain boundaries. Ultrafast nanoscopic dynamics enable quantification of the growth rate and bound the nucleation rate. Finally, we deterministically anchor photo-induced nucleation to predefined nanoscopic regions by locally enhancing the electric field of pump radiation using nano-antennas and monitor the on-demand emergent metallicity in space and time. [1] A.J. Sternbach et al., \textit{Science}\textbf{,} \textbf{371}, 617 (2021). [2] A.J. Sternbach et al.,\textit{ Nano Letters, }DOI: 10.1021/acs.nanolett.1c02638 (2021). [Preview Abstract] |
Saturday, December 4, 2021 10:24AM - 10:36AM |
C01.00004: Polarization Selectivity of Aloof-Beam Electron Energy-Loss Spectroscopy Sobhit Singh, Yao-Wen Yeh, David Vanderbilt, Philip E. Batson Scanning transmission electron microscopy (STEM) coupled with electron energy-loss spectroscopy (EELS) is widely used to probe the electronic properties of materials. In a recent work [1], we demonstrated that the aloof-beam EELS offers good polarization selectivity to detect the orientation-specific interband electronic transitions in one-dimensional ZnO nanorods without the requirement of sample reorientation. In particular, we experimentally observed the key anisotropic features at 11.2 and 13.0 eV differentiating the in-plane (\textbf{\textit{E}} $\bot $ to $c $axis) and out-of-plane (\textbf{\textit{E}} $\parallel $ to $c $axis) responses of wurtzite-ZnO nanorods to an external electric field (\textbf{\textit{E}}), as predicted by our density-functional theory calculations. We further observed some degree of orientation dependence at the onset of direct band gap transition near 3.4 eV, which was attributed to the splitting of the O-2p$_{xy}_{\, }$and O-2p$_{z}_{\, }$occupied states in the wurtzite structure. The fact that good polarization selectivity can be achieved by aloof-beam EELS while keeping the beam-to-specimen orientation fixed broadens the scope of the aloof-beam EELS technique for characterization of nanomaterials. [1] Yao-Wen Yeh, Sobhit Singh, David Vanderbilt, and Philip E. Batson, Phys. Rev. Applied 16, 054009 (2021). [Preview Abstract] |
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