Electroreflectance and Absorption-Edge Studies of AgGaS2and AgGaSe2

摘要: The electroreflectance spectrum of AgGa${\mathrm{Se}}_{2}$ reveals the existence three closely spaced valence bands derived from $p$-like ${\ensuremath{\Gamma}}_{15}$ level zinc-blende compounds under simultaneous effect spin-orbit coupling and noncubic crystalline field. crystal field splitting is shown to result tetragonal distortion chalcopyrite lattice alone. observed considerably less than expected for $p$ levels, a which we attribute \ensuremath{\sim}16% hybridization Ag $4d$ levels with otherwise band. Owing cancellation $d$-like splittings in AgGa${\mathrm{S}}_{2}$, net linewidths structure, transitions only two (split by field) are observed. absorption edges both AgGa${\mathrm{S}}_{2}$ dichroic amounts consistent measurements.