Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- Accelerated computing (1)
- Artificial neural networks (1)
- Charge-density-waves (1)
- Density response function (1)
- Electron-phonon interactions (1)
-
- Electronic (1)
- Ineastic neutron scattering (1)
- Local dynamics (1)
- Magnetic (1)
- Metallic glasses (1)
- Metallic liquids (1)
- Migdal-Eliashberg theory (1)
- Multiferroics (1)
- Spectroscopy (1)
- Structure (1)
- Summit supercomputer (1)
- Superconductivity (1)
- Superlattices (1)
- V2O3 (1)
- Van Hove function (1)
- Vanadium(iii) oxide (1)
- Vibrational (1)
- Publication
Articles 1 - 4 of 4
Full-Text Articles in Physical Sciences and Mathematics
Accelerating Dynamical Density Response Code On Summit And Its Application For Computing The Density Response Function Of Vanadium Sesquioxide, Wileam Y. Phan
Accelerating Dynamical Density Response Code On Summit And Its Application For Computing The Density Response Function Of Vanadium Sesquioxide, Wileam Y. Phan
Masters Theses
This thesis details the process of porting the Eguiluz group dynamical density response computational platform to the hybrid CPU+GPU environment at the Summit supercomputer at Oak Ridge National Laboratory (ORNL) Leadership Computing Center. The baseline CPU-only version is a Gordon Bell-winning platform within the formally-exact time-dependent density functional theory (TD-DFT) framework using the linearly augmented plane wave (LAPW) basis set. The code is accelerated using a combination of the OpenACC programming model and GPU libraries -- namely, the Matrix Algebra for GPU and Multicore Architectures (MAGMA) library -- as well as exploiting the sparsity pattern of the matrices involved in …
Spectroscopic Properties Of Ferroic Superlattices, Shiyu Fan
Spectroscopic Properties Of Ferroic Superlattices, Shiyu Fan
Doctoral Dissertations
The interplay between charge, structure, magnetism, and orbitals leads to rich physics and exotic cross-coupling in multifunctional materials. Superlattices provide a superb platform to study the complex interactions between different degrees of freedom. In this dissertation, I present a spectroscopic investigation of natural and engineered superlattices including FexTaS2 and (LuFeO3)m/(LuFe2O4)1 under external stimuli of temperature and magnetic field as well as chemical substitution. Studying the phase transitions, symmetry-breaking, and complex interface interactions from a microscopic viewpoint enhances fundamental understanding of coupling mechanism between different order parameters and the …
Numerical Studies Of Superconductivity And Charge-Density-Waves: Progress On The 2d Holstein Model And A Superconductor-Metal Bilayer, Philip M. Dee
Numerical Studies Of Superconductivity And Charge-Density-Waves: Progress On The 2d Holstein Model And A Superconductor-Metal Bilayer, Philip M. Dee
Doctoral Dissertations
The problem of superconductivity has been central in many areas of condensed matter physics for over 100 years. Despite this long history, there is still no theory capable of describing both conventional and unconventional superconductors. Recent experimental observations such as the dilute superconductivity in SrTiO3 and near room-temperature superconductivity in hydride compounds under extreme pressure have renewed interest in electron-phonon systems. Adding to this is evidence that electron-phonon coupling may play a supporting role in unconventional systems like the cuprates and monolayer FeSe on SrTiO3.
One way to make sense of these observations is to construct simple …
Local Dynamics And Atomic-Level Structures In Metallic Liquids And Glasses, Zengquan Wang
Local Dynamics And Atomic-Level Structures In Metallic Liquids And Glasses, Zengquan Wang
Doctoral Dissertations
Structure and dynamics at the atomic level in metallic glasses and liquids are poorly understood when compared to the crystalline solids. For instance, even though viscosity is the basic property of liquids, its atomistic origin is not well elucidated. Also, the physics of the fragility of liquids and the crossover phenomenon is far from full understanding. Earlier, through molecular dynamics (MD) simulations a direct connection was found between the timescale describing the macroscopic viscous behavior, the Maxwell relaxation time (tM = h/G∞, h is the shear viscosity and G∞ is the high-frequency shear modulus) and …