The effect of dynamical Bloch oscillations on optical-field-induced current in a wide gap dielectric

TL;DR

This paper investigates how dynamical Bloch oscillations influence the laser-induced current in wide-gap dielectrics, revealing their impact on charge displacement and phase dependence at high laser intensities.

Contribution

It introduces a semiclassical model to analyze the role of Bloch oscillations in charge dynamics under intense laser pulses in wide-gap dielectrics.

Findings

Bloch oscillations significantly affect charge displacement.

Electron waves undergo Bragg-like reflections due to Bloch oscillations.

Charge current dependence on laser phase is altered by these oscillations.

Abstract

We consider the motion of charge carriers in a bulk wide-gap dielectric interacting with a few-cycle laser pulse. A semiclassical model based on Bloch equations is applied to describe the emerging time-dependent macroscopic currents for laser intensities approaching the damage threshold. At such laser intensities, electrons can reach edges of the first Brillouin zone even for electron-phonon scattering rates as high as those known for SiO_2. We find that, whenever this happens, Brag-like reflections of electron waves, also known as Bloch oscillations, affect the dependence of the charge displaced by the laser pulse on its carrier-envelope phase.