Two-photon interband magneto absorption in InSb

Two-photon interband magnetoabsorption in InSb has been studied by measuring the resulting changes in the photoconductivity and free-hole absorption as a function of magnetic field and incident photon energy. In both the photoconductivity and transmission measurements, resonant structure with the peaks occuring at the same values of magnetic field was observed with the incident light polarized both parallel and perpendicular to the magnetic field. The results thus are not in agreement with the existing theories of two-photon magnetoabsorption. A modification to a perturbation theory approach is suggested that appears to explain the experimental observations.