Weak measurement in strong laser field physics

TL;DR

This paper demonstrates that attosecond interferometry can be understood as a form of weak measurement, revealing new phase information in electron dynamics and quantum states during strong laser field interactions.

Contribution

It establishes a connection between weak measurement theory and strong field attosecond physics, highlighting how phase information and quantum features can be accessed and analyzed.

Findings

Electron trajectories acquire a new phase due to weak measurement effects.

Spectral features significantly influence the weak measurement phase contributions.

Non-classical driving fields lead to complex quantum states and photon statistics in generated harmonics.

Abstract

The advantage of attosecond measurements is the possibility of time-resolving ultrafast quantum phenomena of electron dynamics. Many such measurements are of interferometric nature, and therefore give access to the phase. Likewise, weak measurements are intrinsically interferometric and specifically take advantage of interfering probability amplitudes, therefore encoding the phase information of the process. In this work, we show that attosecond interferometry experiments can be seen as a weak measurement, which unveils how this notion is connected to strong field physics and attosecond science. In particular, we show how the electron trajectory picks up a new phase, which occurs due to the weak measurement of the process. This phase can show significant contributions in the presence of spectral features of the measured system. Furthermore, extending this approach to include non-classical driving fields shows that the generated harmonics exhibit non-trivial features in their quantum state and photon statistics. This opens the path towards investigations of attosecond quantum interferometry experiments.