Spin-resolved ARPES

Spin-resolved ARPES extends conventional angle-resolved photoemission spectroscopy by measuring not only the energy and momentum of photoemitted electrons, but also their spin polarization, thereby providing direct access to the spin-dependent electronic structure of a material. This is achieved by directing photoelectrons into a spin polarimeter, where spin-dependent scattering processes reveal the orientation of the electron spin along one or more axes.

By combining momentum, energy, and spin information, spin-resolved ARPES can uncover the spin textures associated with spin-orbit coupling, broken inversion symmetry, magnetic order, and spin-orbital entanglement. The technique has been essential for establishing the helical spin structure of topological surface states, quantifying Rashba and related spin splittings, and revealing subtler forms of entanglement between spin, orbital, and band degrees of freedom in complex quantum materials.

Our group uses spin-resolved ARPES to investigate how spin and orbital character are intertwined in topological, correlated, and spin-orbit-coupled materials, and to connect these observations directly to the underlying symmetry and many-body structure of their electronic states.