Theory of double magnetophonon resonance in a two-dimensional electron gas in a tilted magnetic field

A theory of double magnetophonon resonance (MPR) in quantum wells in magnetic field is developed. The magnetic field is assumed to be tilted at an angle theta to the perpendicular to the plane of quantum well. The resonance is due to the resonant interaction of two-dimensional conduction electrons with the longitudinal optic phonons. The electrons are assumed to be nondegenerate. The theta dependence of MPR maxima is investigated. The existence of a double resonance, i.e., two resonant peaks for each value of N (the number of resonance) and sharpness of the theta dependence is explained by the screening in conjunction with the combined role of the phonon and electon damping and variation of electron concentration in the well with magnetic field.