Spin‐Magnetophonon Resonance in Semiconductors

A theory is presented for spin‐magnetophonon resonance. The spin interaction of electrons with optical phonons is described by the introduction of vector and scalar potentials of the optical vibrational field. It is shown that the spin‐magnetophonon resonance should cause a minimum in the longitudinal magnetoresistance. The experimental data for n‐InSb and n‐InAs are discussed on the basis of this theory. Certain new magnetoresistance measurements are presented for the case of n‐InSb: 1) A maximum of the transverse magnetoresistance is observed at 82 kG corresponding to the spin‐magnetophonon resonance. The g ‐factor for the conduction electrons, calculated from this maximum, is in good agreement with the theoretical value. 2) A minimum in the longitudinal magnetoresistance is observed at 24 kG, dur to the combined magnetophonon and spin‐magnetophonon resonance scattering.