Interplay of orbital angular momentum and chirality
摘要
Orbital physics has become a focus of emerging research in different areas of condensed matter physics. There has been a recent surge of interest in materials exhibiting chirality, owing to its natural connection to the orbital degree of freedom. Although numerous studies have experimentally investigated orbital-induced phenomena, such as the orbital Edelstein and orbital Hall effects, disentangling the contributions of orbital degrees of freedom remains a challenge. Here we discuss how polarization-dependent angle-resolved photoemission spectroscopy can give access to the orbital angular momentum texture in momentum space—a key property for understanding the orbital currents that are essential for orbitronic applications. We further highlight practical examples where dichroic angle-resolved photoemission spectroscopy is used to visualize how the orbital angular momentum intertwines with chiral degrees of freedom. This spectroscopic characterization of their interplay contributes to our understanding of orbital physics in solids and provides valuable insights for the development of chiral orbitronics and spintronics.