Interferometrically Enhanced Asymmetry in Strong-field Ionization with Bright Squeezed Vacuum

TL;DR

This paper shows how nonclassical quantum light, specifically bright squeezed vacuum, can dramatically enhance asymmetries in strong-field ionization, enabling better control and understanding of electron dynamics.

Contribution

It introduces a novel method using bright squeezed vacuum to control tunneling ionization asymmetries, surpassing classical field effects and revealing new pathways for sub-cycle dynamics analysis.

Findings

PMDs exhibit asymmetries exceeding classical fields by orders of magnitude.

The effect is linked to nonclassical statistics of the BSV field.

Fluctuations in the instantaneous field amplitude modify tunneling probabilities.

Abstract

We demonstrate that quantum light statistics can be used to control strong-field ionization at the tunneling step. Using a bichromatic linearly polarized field composed of a strong coherent driver and a weak bright squeezed vacuum (BSV), we show through simulation that photoelectron momentum distributions (PMDs) exhibit asymmetries that exceed those obtained with classical fields of comparable intensity by orders of magnitude. This enhancement is uniquely linked to the nonclassical statistics of the BSV field. A semiclassical analysis based on the strong-field approximation (SFA) reveals that the effect originates from fluctuations in the instantaneous field amplitude, which strongly modify the tunneling ionization probability while leaving the electron's continuum dynamics essentially unchanged. This selective control enables reconstruction of ionization pathways and provides a robust route to extract sub-cycle dynamics from strong-field observables.