Related papers: Frequency dependent magneto-optical conductivity i…
The $\alpha$-$T_3$ system undergoes a topological phase transition(TPT) between two distinct quantum spin-Hall phases across $\alpha=0.5$ when the spin-orbit interaction of Kane-Mele type is taken into consideration. As a hallmark of such a…
The generalized tight-binding model, being based on the spin-dependent sublattices, is developed to explore the magnetic quantization of monolayer bismuthene. The sp$^{3}$ orbital hybridizations, site energies, nearest and next-nearest…
Flat bands underlie a diverse range of quantum phenomena, from strongly correlated phases to superconductivity. We theoretically establish that a two-dimensional electron gas under a linear magnetic-field gradient and a transverse electric…
Using Linear Response Theory, with appropriate wave functions and energies from perturbation method, the absorption profiles can be calculated for all three classes of mixed-valence systems as defined by Robin and Day : Class III…
We generalize the construction of time-reversal symmetry-breaking triple-component semimetals, transforming under the pseudospin-1 representation, to arbitrary (anti-)monopole charge $2 n$, with $n=1,2,3$ in the crystalline environment. The…
In a system with a Dirac-like linear dispersion there are always states that fulfill the resonance condition for electromagnetic radiation of arbitrary frequency $\Omega$. When a flat band is present two kinds of resonant transitions are…
Massless Dirac fermions occur as low-energy modes in several quasi-two-dimensional condensed matter systems such as graphene, the surface of bulk topological insulators, and in layered organic semiconductors. When the rotational symmetry in…
We show that the position-momentum duality offers a transparent interpretation of the band geometry at the topological band crossings. Under this duality, the band geometry with Berry connection is dual to the free-electron motion under…
The three-dimensional magneto-conductivity tensor was derived in a gauge invariant form based on the Kubo formula considering the quantum effect under a magnetic field, such as the Landau quantization and the quantum oscillations. We…
A semiclassical quantization condition is derived for Landau levels in general spin-orbit coupled systems. This generalizes the Onsager quantization condition via a matrix-valued phase which describes spin dynamics along the classical…
We study the frequency-dependent magnetoconductivity of a strongly correlated nondegenerate 2D electron system in a quantizing magnetic field. We first restore the single-electron conductivity from calculated 14 spectral moments. It has a…
We analyze the Landau level (LL) structure and spin Hall effect in a MoS2 trilayer. Due to orbital asymmetry, the low-energy Dirac fermions become heavily massive and the LL energies grow linearly with $B$, rather than with $\sqrt{B}$.…
We present general design principles for engineering and discovering periodic systems with flat bands. Our paradigm exploits spin-orbit assisted orbital frustration on a lattice to produce band structures that contain multiplets of narrowly…
We predict that spin-waves in an ordered square quantum antiferromagnet in a transverse magnetic field (h) may demonstrate three modes of spin excitations. Starting from the self-consistent rotation-invariant Green's function method, a new…
The field dependence of interlayer magnetoresistance of the pressurized (to the normal state) layered organic metal $\alpha $-(BEDT-TTF)$_{2}$KHg(SCN)$_{4}$ is investigated. The high quasi-two-dimensional anisotropy, when the interlayer…
We present a theoretical description of the interlayer magnetoresistance in the layered Dirac fermion system with the application to the organic conductor \alpha-(BEDT-TTF)_2I_3 under pressure. Assuming a non-vertical interlayer tunneling…
We investigate optical transitions of non-interacting electron systems consisting of two symmetric energy bands touching each other at the Fermi energy (e.g. graphene at half filling). Optical conductivity is obtained using Kubo formula at…
We investigate the S=1/2 antiferromagnetic Heisenberg model with a 3$\times$3 checkerboard lattice structure in a longitudinal magnetic field. By using the stochastic series expansion quantum Monte Carlo (SSE-QMC) method, we obtain the…
In this paper we study the energy spectrum of a two dimensional electron gas (2DEG) in a two dimensional periodic magnetic field. Both a square magnetic lattice and a triangular one are considered. We consider the general case where the…
We compute the longitudinal electrical conductivity in the presence of strong background magnetic field in complete leading order of perturbative QCD, based on the assumed hierarchy of scales $\alpha_s eB\ll (m_q^2,T^2)\ll eB$. We formulate…