Disentangle electronic, structural, and spin dynamics using transient extreme ultraviolet spectroscopy

Abstract

Understanding the coupled microscopic interactions in complex materials offers key insights into realizing the functions of new materials. As an emerging spectroscopic technique in materials science, transient extreme ultraviolet (XUV) spectroscopy can measure the element-specific chemical dynamics with femtosecond and even attosecond time resolution. It has the potential to simultaneously capture the coupled charge, lattice, and spin dynamics in a single measurement. In this review, we discuss the technical advantages of transient XUV spectroscopy. We aim to understand the ultrafast carrier, lattice, and spin dynamics that are important for future renewable energy and optoelectronics applications. We emphasize that transient XUV spectroscopy can not only measure these dynamics with high precision, but also is sensitive to the interaction and coupling between these different degrees of freedom. Examples include electron–phonon coupling during polaron formation and Peierls distortion, phonon–phonon scattering in graphite, and electron–spin dynamics in light-induced spin transfer. The ability to extract electron–phonon coupling, phonon–phonon scattering, and electron–spin coupling in a single transient XUV measurement paves the way toward future applications in strongly correlated phenomena and chemical dynamics in complex environments.