Probing the energy conversion pathways between light, carriers and lattice in real time with attosecond core-level spectroscopy

TL;DR

This paper introduces a novel attosecond core-level X-ray spectroscopy technique that can real-time probe energy transfer processes between light, charge carriers, and the lattice in materials, revealing mechanisms across femtosecond to picosecond timescales.

Contribution

The study presents a new methodology using attosecond core-level spectroscopy to distinguish and analyze energy conversion pathways in materials with unprecedented temporal resolution.

Findings

Revealed carrier-specific dephasing mechanisms in graphite

Demonstrated detection of energy flow dynamics on femtosecond to picosecond scales

Validated the method's ability to disentangle overlapping processes

Abstract

Detection of the energy conversion pathways, between photons, charge carriers, and the lattice is of fundamental importance to understand fundamental physics and to advance materials and devices. Yet, such insight remains incomplete due to experimental challenges in disentangling the various signatures on overlapping time scales. Here, we show that attosecond core-level X-ray spectroscopy can identify these interactions with attosecond precision and across a picosecond range. We demonstrate this methodology on graphite since its investigation is complicated by a variety of mechanisms occurring across a wide range of temporal scales. Our methodology reveals, through the simultaneous real-time detection of electrons and holes, the different dephasing mechanisms for each carrier type dependent on excitation with few-cycle-duration light fields. These results demonstrate the general ability of our methodology to detect and distinguish the various dynamic contributions to the flow of energy inside materials on their native time scales.