A5101658217- Graphene research and applications
- Quantum and electron transport phenomena
- Topological Materials and Phenomena
- Quantum, superfluid, helium dynamics
- Advanced Condensed Matter Physics
- Quantum many-body systems
- Magnetic properties of thin films
- Carbon Nanotubes in Composites
- Physics of Superconductivity and Magnetism
University of Kentucky
2021-2023
We study the edge spectrum of twisted sheets single layer and bilayer graphene in cases where continuum model predicts a valley Chern insulator---an insulating state which occupied moir\'e mini-bands from each have net number, but both valleys together no as required by time-reversal symmetry. In simple picture, such might be expected to chiral polarized counterpropagating states. present results exact diagonalization tight-binding commensurate structures ribbon geometry. find that for...
Inspired by experiments on magic angle twisted bilayer graphene, we present a lattice mean-field model for the quantum anomalous Hall effect in moir\'e setting. Our hopping thus provides simple route to Chern insulator commensurately models. We study of our ribbon geometry, which demonstrate presence thick chiral edge states that have transverse localization scales with spacing. also electronic structure domain wall between opposite insulators. and results are relevant will image or...
We propose a device in which sheet of graphene is coupled to Weyl semimetal, allowing for the physical access study tunneling from two- three-dimensional massless Dirac fermions. Because reconstructed band structure, we find that this acts as robust valley filter electrons sheet. show that, by appropriate alignment, semimetal draws away current one two valleys, while other pass unimpeded. In contrast proposed filters, mechanism our occurs bulk sheet, obviating need carefully shaped edges or...
We predict that the gapless $U(1)$ Dirac spin liquid naturally emerges in a two-dimensional array of quantum dipoles. In particular, we demonstrate dipolar XY model$\unicode{x2014}$realized both Rydberg atom arrays and ultracold polar molecules$\unicode{x2014}$hosts ground state on kagome lattice. Large-scale density matrix renormalization group calculations indicate this exhibits signatures gapless, linearly-dispersing spinons, consistent with liquid. identify route to adiabatic preparation...
We investigate the spontaneous disintegration of magnons in two-dimensional ferromagnets and antiferromagnets dominated by long-range dipolar interactions. Analyzing kinematic constraints, we show that unusual dispersion a uniform magnetic field precludes magnon-decay at all fields, sharp contrast to short-range exchange-driven magnets. However, staggered field, used for state preparation recent Rydberg array experiments, can decay both antiferromagnets. Remarkably, such decays do not...
We study the edge spectrum of twisted sheets single layer and bilayer graphene in cases where continuum model predicts a valley Chern insulator -- an insulating state which occupied moiré mini-bands from each have net number, but both valleys together no as required by time reversal symmetry. In simple picture, such might be expected to chiral polarized counter-propagating states. present results exact diagonalization tight-binding commensurate structures ribbon geometry. find that for...
Inspired by experiments on magic angle twisted bilayer graphene, we present a lattice mean-field model for the quantum anomalous Hall effect in moiré setting. Our hopping thus provides simple route to Chern insulator commensurately models. We study of our ribbon geometry, which demonstrate presence thick chiral edge states that have transverse localization scales with spacing. also electronic structure domain wall between opposite insulators. and results are relevant will image or manipulate states.