Laser induced phase transition in epitaxial FeRh layers studied by pump-probe valence band photoemission

TL;DR

This study employs time-resolved X-ray photoelectron spectroscopy to investigate ultrafast laser-induced phase transitions in FeRh films, revealing rapid magnetic and electronic changes within 50-100 ps.

Contribution

It provides new experimental and theoretical insights into the electronic structure and magnetic dynamics during laser-induced phase transitions in FeRh.

Findings

Magnetic transition occurs in less than 50 ps

Spin-polarized feature at Fermi edge indicates magnetic state

Transition reaches maximum in approximately 100 ps

Abstract

We use time-resolved X-ray photoelectron spectroscopy to probe the electronic and magnetization dynamics in FeRh films after ultrafast laser excitations. We present experimental and theoretical results which investigate the electronic structure of the FeRh during the first-order phase transition identifying a clear signature of the magnetic phase. We find that a spin polarized feature at the Fermi edge is a fingerprint of the magnetic status of the system that is independent of the long-range ferromagnetic alignment of the magnetic domains. We use this feature to follow the phase transition induced by a laser pulse in a pump-probe experiment and find that the magnetic transition occurs in less than 50 ps, and reaches its maximum in 100 ps.