Strong-Field Resonant Dynamics in Semiconductors

TL;DR

This paper predicts a new regime of electron dynamics in semiconductors under strong ultrashort laser pulses, involving resonant anharmonic Rabi oscillations coupled with intraband motion, leading to phase-controlled currents.

Contribution

It introduces the concept of kicked anharmonic Rabi oscillations (KARO) in semiconductors, revealing novel electron dynamics under strong-field excitation.

Findings

Prediction of KARO regime in GaAs under strong laser pulses

Identification of phase-controlled electric currents due to population asymmetry

Potential for experimental observation via photoemission and terahertz spectroscopy

Abstract

We predict that a direct bandgap semiconductor (GaAs) resonantly excited by a strong ultrashort laser pulse exhibits a novel regime: kicked anharmonic Rabi oscillations (KARO). In this regime, Rabi oscillations are strongly coupled to intraband motion, and interband transitions mainly take place during short times when electrons pass near the Brillouin zone center where electron populations undergo very rapid changes. Asymmetry of the residual population distribution induces an electric current controlled by the carrier-envelope phase. The predicted effects are experimentally observable using photoemission and terahertz spectroscopies.