Related papers: Reentrant Quantum Spin Hall States in Charge Densi…
Recent experiments suggest that low carrier density three-dimensional (3D) metals ZrTe$_5$ and HfTe$_5$ exhibit the 3D quantum Hall (QH) effect with Hall resistivity plateaus and a metal-insulator transition in strong magnetic fields. The…
The semimetallic or semiconducting nature of the transition metal dichalcogenide 1$T$-TiSe$_2$ remains under debate after many decades mainly due to the fluctuating nature of its 2 $\times$ 2 $\times$ 2 charge-density-wave (CDW) phase at…
We perform density matrix renormalization group (DMRG) calculations extensively on one-dimensional chains with on site (U) as well as nearest neighbour (V) Coulomb repulsions. The calculations are carried out in full parameter space with…
Recent experimental progress has established the twisted bilayer transition metal dichalcogenide (TMD) as a highly tunable platform for studying many-body physics. Particularly, the homobilayer TMDs under displacement field are believed to…
An incommensurate charge density wave (CDW) is a periodic modulation of charge that breaks translational symmetry incongruently with the underlying lattice. Its low-energy excitations, the phason, are collective, gapless phase fluctuations.…
We study the magnetic phases of two coupled two-dimensional electron gases in order to determine under what circumstances these phases may occur in real semiconductor quantum wells and what the experimental properties of the broken-symmetry…
We study the emergence of the quantum spin Hall (QSH) states for the pseudo-gap (PG) phase of Bi2212 bilayer system, assumed to be D-density wave(DDW) ordered, starting with a strong Rashba spin-orbit coupling(SOC) armed, and the time…
The recently discovered FeAs-based materials exhibit a $(\pi,0)$ Spin Density Wave (SDW) in the undoped state, which gives way to superconductivity upon doping. Here we show that due to an interesting topological feature of the band…
It has been demonstrated that topological quantum spin Hall (QSH) state exist in twisted bilayers of transition metal dichalcogenides. However, a comprehensive theoretical characterization of the topological edge states remains a topic of…
The spin current density functional theory (SCDFT) is the generalization of the standard DFT to treat a fermionic system embedded in the effective external field produced by the spin-orbit coupling interaction. Even in the absence of a spin…
By using scanning tunneling microscopy (STM) / spectroscopy (STS), we systematically characterize the electronic structure of lightly doped 1T-TiSe2, and demonstrate the existence of the electronic inhomogeneity and the pseudogap state. It…
I employ a semiphenomenological model introduced in A. M. Tsvelik, A. V. Chubukov, Phys. Rev. Lett. {\bf 98}, 237001 (2007) to describe the state with co-existing superconductivity (SC) and charge density wave (CDW) recently discovered in…
The recent discovery of topological Dirac semimetals (DSM) has provoked intense curiosity not only on Weyl physics in solids, but also on topological phase transitions originating from DSM. One example is controlling the dimensionality to…
Using {\it ab initio} density functional theory, we study the lattice phase transition of quasi-one-dimensional (TaSe$_4$)$_2$I. In the undistorted state, the strongly anisotropic semimetal band structure presents two non-equivalent Weyl…
Recently two interesting candidate quantum phases --- the chiral spin density wave state featuring anomalous quantum Hall effect and the d+id superconductor --- were proposed for the Hubbard model on the honeycomb lattice at 1/4 doping.…
In low-disorder, two-dimensional electron systems (2DESs), the fractional quantum Hall states at very small Landau level fillings ($\nu$) terminate in a Wigner solid (WS) phase, where electrons arrange themselves in a periodic array. The WS…
Transition metal dichalcogenides (TMDs), exhibit a range of crystal structures and topological quantum states. The 1$T$ phase, in particular, shows promise for superconductivity driven by electron-phonon coupling, strain, pressure, and…
The search for topologically non-trivial states of matter has become an important goal for condensed matter physics. Recently, a new class of topological insulators has been proposed. These topological insulators have an insulating gap in…
The layered transition metal dichalcogenides host a rich collection of charge density wave (CDW) phases in which both the conduction electrons and the atomic structure display translational symmetry breaking. Manipulating these complex…
Charge density wave (CDW) formation in two-dimensional materials is governed by complex competing lattice instabilities that remain incompletely understood. Here, we investigate the structural evolution of monolayer $\mathrm{1T-VSe}_{2}$…