New bound spin-flip transitions in n-InSb

Donor spin - flip transitions with ΔN = 0, ΔM = ?1, and Δλ = 1 are observed in InSb in high magnetic fields using an optically pumped far-infrared laser system. Variational calculations of the donor levels yielded good agreement with previously observed donor transitions energies. As regards the new spin - flip transitions reported in this work, the theoretical treatment has to be revised particularly for obtaining correct selection rules.