Two‐Phonon Resonance Raman Scattering and Quantum Interference Effects in Polar Semiconductors in High Magnetic Fields

The EHP contribution to the two‐phonon resonance Raman scattering (RRS) cross‐section is calculated for a polar semiconductor located in a high magnetic field H . This contribution is of order α, where α is the Fröhlich electron (hole)‐LO phonon coupling constant (in the case H = 0 the cross section is of order α 2 ). This α‐dependence results from the quasi one‐dimensional motion of the electron (hole) in a high magnetic field. For such a polar semiconductor as InSb (α ≈ 0.013 ≪ ≪ 1) a high magnetic field leads to a sharp increase of the secondary radiation intensity. The two‐phonon RRS cross section is an oscillating function of the magnetic field H and (or) of the incident light frequency ω 1 . The oscillations exist due to the increase of the density of states near the Landau zone bottom. It is shown that in the vicinity of a number of values of the magnetic field H = H 0 / L , where H 0 = m e c ωLO/|e|, ( m e ( e ) = effective mass (charge) of electron, L = 1/2, 1, 3/2, 2, …, there is a number of additional contributions of interferential character to the cross section, which lead to a resonance decrease of the secondary emission intensity.