Green's functions of electrons in group-VI dichalcogenides in a magnetic field

TL;DR

This paper derives an explicit Green's function for electrons in group-VI dichalcogenides under a magnetic field, enabling analysis of local density of states and impurity effects in these materials.

Contribution

It provides a closed-form Green's function expression using Whittaker functions for electrons in dichalcogenides in magnetic fields, a novel analytical result.

Findings

Green's function expressed as an 8x8 matrix with valley and spin distinctions

Calculation of local density of states near impurities showing oscillations or decay

Application of the Green's function to impurity-induced electron density analysis

Abstract

Closed expression for the Green's function of the stationary two-dimensional Schrodinger equation for an electron in group-VI dichalcogenides in the presence of a magnetic field is obtained in terms of the Whittaker functions. The resulting Green's function operator is a~$8 \times 8$ matrix consisting of four block-diagonal~$2\times 2$ matrices, each of them characterized by different values of valley index and electron spin. The obtained results are used to calculate local density of states induced by a neutral delta-like impurity in the presence of a magnetic field within the lowest Born approximation. The spatial electron density experiences either the Friedel-like oscillations or an exponential decay as a function of the distance from the impurity.