Probe of the Band Structure of MBE Grown p-Type InMnAs at Ultrahigh Magnetic Fields

Abstract

We present a theoretical and experimental study on electronic and magneto-optical properties of p-type paramagnetic InMnAs dilute magnetic semiconductor (DMS) alloys in ultrahigh (> 100 T) external magnetic fields (B). Theoretical calculations are based on an 8-band Pidgeon–Brown model which is generalized to include the wavevector dependence of the electronic states along B as well as s–d and p–d exchange interactions with localized Mn d-electrons. The spin-dependent electronic structure as a function of Mn doping is computed and the dependence of the valence band structure on parameters such as the sp–d exchange interaction strength and effective masses in paramagnetic p- InMnAs alloys are examined. The cyclotron resonance (CR) and magneto-optical properties of InMnAs are calculated using Fermi's golden rule. Two strong CR peaks are observed in p-type InMnAs alloys which correspond to the transitions within either heavy-hole (HH) or light-hole (LH) Landau levels. Furthermore, we also observed strong resonance absorption for electron-active polarization which can occur in p-type semiconductors originating from transitions between the light and heavy hole Landau levels.