A5020224221- Quantum and electron transport phenomena
- Physics of Superconductivity and Magnetism
- Magnetic properties of thin films
- Advanced Chemical Physics Studies
- Graphene research and applications
- Quantum, superfluid, helium dynamics
- Topological Materials and Phenomena
- Cold Atom Physics and Bose-Einstein Condensates
- Semiconductor Quantum Structures and Devices
- Spectroscopy and Quantum Chemical Studies
- Molecular Junctions and Nanostructures
- Surface and Thin Film Phenomena
- Electronic and Structural Properties of Oxides
- Advanced Physical and Chemical Molecular Interactions
- Advanced Thermodynamics and Statistical Mechanics
- Magnetic and transport properties of perovskites and related materials
- Advanced Condensed Matter Physics
- Mechanical and Optical Resonators
- Atomic and Subatomic Physics Research
- Machine Learning in Materials Science
- Thermal properties of materials
- Theoretical and Computational Physics
- Semiconductor materials and devices
- Quantum many-body systems
- Plasmonic and Surface Plasmon Research
University of Missouri
2016-2025
National University of Singapore
2018-2025
Institute of Molecular Functional Materials
2025
Yale-NUS College
2018-2022
University of Oslo
2022
Indian Institute of Technology Mandi
2022
Indian Institute of Technology Kharagpur
2022
HAW Hamburg
2020
Universität Hamburg
2020
University of Manchester
2020
We formulate the current-density--functional theory for systems in arbitrarily strong magnetic fields. A set of self-consistent equations comparable to Kohn-Sham ordinary density-functional is derived, and proved be gauge invariant satisfy continuity equation. prove that exchange-correlation energy functional ${\mathrm{E}}_{\mathrm{xc}[\mathrm{n}}$,${\mathrm{j}}_{\mathrm{p}}$] [n(r) density ${\mathrm{j}}_{\mathrm{p}}$(r) ``paramagnetic'' current density] depends on via combination...
The frequency-dependent exchange-correlation potential, which appears in the usual Kohn-Sham formulation of a time-dependent linear response problem, is strongly nonlocal functional density, so that consistent local density approximation generally does not exist. This problem can be avoided by choosing current as basic variable generalized theory. theory admits which, for fixed frequency, exact limit slowly varying densities and perturbing potentials.
We formulate the current- and spin-density-functional theory for electronic systems in arbitrarily strong magnetic fields. A set of single-particle self-consistent equations which determine, addition to ground-state energy, density, spin current spin-current is derived proved be gauge invariant satisfy various physical requirements, including continuity equation. For a field constant direction space, we prove that exchange-correlation energy functional...
We provide a precise microscopic definition of the recently observed "Inverse Edelstein Effect" (IEE), in which non-equilibrium spin accumulation plane two-dimensional (interfacial) electron gas drives an electric current perpendicular to its own direction. The drift-diffusion equations that govern effect are presented and applied interpretation experiments.
In the current density functional theory of linear and nonlinear time-dependent phenomena, treatment exchange correlation beyond level adiabatic local approximation is shown to lead appearance viscoelastic stresses in electron fluid. Complex frequency-dependent viscosity/elasticity coefficients are microscopically derived expressed terms properties homogeneous gas. As a first consequence this formalism, we provide an explicit formula for linewidths collective excitations electronic systems.
Based on standard perturbation theory, we present a full quantum derivation of the formula for orbital magnetization in periodic systems. The is generally valid insulators with or without Chern number, metals at zero finite temperatures, and weak as well strong magnetic fields. shown to be presence electron-electron interaction, provided one-electron energies wave functions are calculated self-consistently within framework exact current spin-density functional theory.
Electrons in artificial lattices enable explorations of the impact repulsive Coulomb interactions a tunable system. We have trapped two-dimensional electrons belonging to gallium arsenide quantum well nanofabricated lattice with honeycomb geometry. probe excitation spectrum magnetic field identifying novel collective modes that emerge from interaction as predicted by Mott-Hubbard model. These observations allow us determine Hubbard gap and suggest existence Coulomb-driven ground state. This...
At low energy, electrons in doped graphene sheets behave like massless Dirac fermions with a Fermi velocity, which does not depend on carrier density. Here we show that modulating two-dimensional electron gas long-wavelength periodic potential honeycomb symmetry can lead to the creation of isolated points tunable velocity. We provide detailed theoretical estimates realize such artificial graphenelike system and discuss an experimental realization modulation-doped GaAs quantum well....
Using time-dependent current-density functional theory, we derive analytically the dynamical exchange-correlation correction to dc conductance of nanoscale junctions. The pertains calculated in zero-frequency limit density theory within adiabatic local-density approximation. In particular, show that linear response, depends nonlinearly on gradient electron density; thus, it is more pronounced for molecular junctions than quantum point contacts. We provide specific numerical examples...
We demonstrate that the plasmon frequency and Drude weight of electron liquid in a doped graphene sheet are strongly renormalized by electron-electron interactions even long-wavelength limit. This effect is not captured random-phase approximation (RPA), commonly used to describe fluids, due coupling between center-of-mass motion pseudospin degree freedom graphene's massless Dirac fermions. By making use diagrammatic perturbation theory first order interaction, we show this enhances both...
Hydrodynamic flow occurs in an electron liquid when the mean free path for electron-electron collisions is shortest length scale problem. In this regime, transport described by Navier-Stokes equation, which contains two fundamental parameters, bulk and shear viscosities. Article we present extensive results these coefficients case of two-dimensional massless Dirac fermion a doped graphene sheet. Our approach relies on microscopic calculations viscosities up to second order strength...
An intriguing property of a three-dimensional (3D) topological insulator (TI) is the existence surface states with spin-momentum locking, which offers new frontier exploration in spintronics. Here, we report observation type Hall effect 3D TI ${\mathrm{Bi}}_{2}{\mathrm{Se}}_{3}$ film. The resistance scales linearly both applied electric and magnetic fields exhibits $\ensuremath{\pi}/2$ angle offset respect to its longitudinal counterpart, contrast usual $\ensuremath{\pi}/4$ between linear...
Spin-orbitronics, which exploits the coupling between spin and orbital momentum of electrons, relies on possibility to electrically create detect pure currents without need ferromagnetic elements. An efficient way achieve this spin-to-charge conversion (and vice versa) is expected by exploiting Rashba-Edelstein effect. This phenomenon related well-known Hall effect, but in former, current occurs at interface materials with a strong splitting surface states, instead bulk. paper reports an...
The authors show that the valley Hall effect in gapped graphene can be understood as a manifestation of orbital effect, which electrons states opposite magnetic moment flow directions, generating an magnetization current. Replacing ambiguous indices by physical quantity -- this reformulation provides convincing explanation optical rotation measurements graphene.
Graphene sheets encapsulated between hexagonal Boron Nitride (hBN) slabs display superb electronic properties due to very limited scattering from extrinsic disorder sources such as Coulomb impurities and corrugations. Such samples are therefore expected be ideal platforms for highly-tunable low-loss plasmonics in a wide spectral range. In this Article we present theory of collective electron density oscillations graphene sheet two hBN semi-infinite (hBN/G/hBN). plasmons hybridize with...
Recent experiments have revealed nonlinear features of the magnetoresistance in metallic bilayers consisting a heavy metal (HM) and ferromagnetic (FM). A small change longitudinal resistance bilayer has been observed when reversing direction either applied in-plane current or magnetization. We attribute such transport behavior to spin-polarization dependence electron mobility FM layer acting concert with spin accumulation induced that by Hall originating bulk HM layer. An explicit expression...
Using an effective Dirac model, we study the orbital Hall effect (OHE) in bilayers of transition metal dichalcogenides with 2H stacking (2H-TMD). We use first-order perturbation theory interlayer coupling bilayer system to obtain analytical expressions for conductivity linear response regime. two distinct descriptions angular momentum (OAM) operator. The first one is intra-atomic approximation that considers only intrasite contribution OAM [Cysne et al., Phys. Rev. Lett. 126, 056601 (2021)]....