Acceptor identification using magnetophotoluminescence of bound exciton states in InSb

Photoluminescence measurements were performed on Czochralski-grown indium antimonide samples in magnetic fields up to 7 T using a cryogenically cooled interferometer. Principal acceptor bound exciton luminescence and corresponding two-hole transitions (THT) were observed for both p-type and n-type samples. THT corresponding to the 2S(3/2) excited states of the acceptor were observed in Cd-doped and Ge-doped InSb samples, and the photoluminescence of the two acceptors can be distinctly resolved with a separation of 1.6 cm(-1) at 1 T. For magnetic fields above 1 T, excitations to the 2P(5/2) and 3S(3/2) states were also observed. The Zeeman splittings for all of the THT were mapped as a function of magnetic field, and zero-field energies for the acceptor excited states 2S(3/2)(Gamma(8)), 3S(3/2)(Gamma(8)), 2P(5/2)(Gamma(8)), and 2P(5/2)(Gamma(7)) were measured for both the Ge and Cd acceptors. Using the energy separation of the principal bound exciton luminescence and the THT luminescence from the 2P(5/2)(Gamma(7)) excited state along with the theoretically calculated binding energy for the 2P(5/2)(Gamma(7)) state, acceptor binding energies of 79.2 and 80.5 cm(-1) were established for Ge and Cd, respectively. The THT for the 2S(3/2)(Gamma(8)) excited state of a third, unidentified acceptor (A(3)) were observed, and a binding energy of 106.9 cm(-1) was determined.