Shubnikov-de Haas effect in n-CdSb:In under pressure

摘要

Magnetoresistance (MR) of single crystals of the group Ⅱ-Ⅴ semiconductor n-CdSb doped with In is investigated in magnetic fields B up to 7 T and temperatures T between 1.2 and 2.4 K under hydrostatic pressure p = 0-10 kbar. Shubnikov-de Haas (SdH) oscillations of MR observed up to B ～ 4 T are characterized by a single period, giving evidence for one participating group of conduction band electrons. Pressure dependence of the SdH period and concentration reveal a second group of charge carriers, connected to a resonance impurity band with delocalized states. The SdH amplitude, A, exhibits non-universal behavior attributable to its sensitivity to scattering mechanism at low quantum numbers. The parameters characterizing the non-universality of A(T) and the pressure dependence of the cyclotron effective mass, m_c(p), and of the concentration of conduction electrons, n_(SdH), are given. The dependences of m_c and the Fermi energy on pressure are consistent with Kane-type non-parabolicity of the conduction band.