Steady-State Density of States for Electrons in Terahertz-Driven One-Dimensional Electron Gases

Abstract

A detailed theoretical study of the density of states (DOS) is presented for free electrons in one-dimensional electron gases (1DEGs), subject to terahertz (THz) electromagnetic (EM) fields polarised linearly. Applying the solution of time-dependent Schrödinger equation in a specific sample configuration, where electron interactions with the radiation field can be included exactly, I have derived the two-time Green's function, and from it the steady-state DOS for a THz-driven 1DEG is obtained. The results show that the presence of the intense THz EM radiations will result in a strong modulation of the DOS for electrons in 1DEGs. It has been found that the optical processes via photon emission and absorption, including the multiphoton channels, will affect significantly the electron DOS in a 1DEG system.