Attosecond Coherent Electron Motion in Auger-Meitner Decay

TL;DR

This paper demonstrates the use of attosecond soft x-ray pulses and infrared laser pulses to induce, control, and time-resolve coherent electron motion in core-excited nitric oxide, advancing ultrafast quantum dynamics studies.

Contribution

It introduces a novel method combining attosecond x-ray pulses and infrared lasers to control and observe coherent electron dynamics in molecules.

Findings

Controlled electron motion in nitric oxide achieved.

Tuning photon energy influences electron dynamics.

First demonstration of attosecond x-ray pulse application in core-hole excitation.

Abstract

In quantum systems, coherent superpositions of electronic states evolve on ultrafast timescales (few femtosecond to attosecond, 1 as = 0.001 fs = 10^{-18} s), leading to a time dependent charge density. Here we exploit the first attosecond soft x-ray pulses produced by an x-ray free-electron laser to induce a coherent core-hole excitation in nitric oxide. Using an additional circularly polarized infrared laser pulse we create a clock to time-resolve the electron dynamics, and demonstrate control of the coherent electron motion by tuning the photon energy of the x-ray pulse. Core-excited states offer a fundamental test bed for studying coherent electron dynamics in highly excited and strongly correlated matter.