The first magneto-optical transitions originating from a deep defect level in high-purity n-InSb are observed in the CO2-laser-induced resonant photoconductivity at low magnetic fields. Another series of resonant structures is associated with three-LO-phonon-assisted spin-conserving cyclotron harmonic transitions.
SEILER, D. G., GOODWIN, M. W., & MILLER, A. (1980). RESONANT MAGNETO-OPTICAL TRANSITIONS FROM A MID-GAP LEVEL IN N-INSB. Physical Review Letters, 44(12), 807-810. https://doi.org/10.1103/PhysRevLett.44.807