Measurement of energy distribution of conduction electrons in superlattice by visible-light photoemission spectroscopy

Visible-light photoemission spectroscopy (VPS) is a novel angle-resolved photoemission spectroscopy developed by us for measuring conduction electrons emitted from a surface with negative electron affinity state. In this study, InGaAs/GaAsP quantum well superlattice was analyzed by the VPS method with changing the excitation photon energy. By comparing with comparison of the energy distribution curves obtained by different excitation energy, the first and second conduction mini-band structures were directly clarified.