Resonance modulation of the intersubband electron-electron interaction in an AlSb(δ-Te)/InAs/AsSb(δ-Te) quantum well by magnetic field

The amplitude-frequency modulation of oscillations of the magnetoresistance of 2D electrons in an AlSb(δ-Te)/InAs/AsSb(δ-Te) quantum well is studied. In the dependence of the amplitude of the oscillations δ(1/B) _{T = const}, regions of negative Dingle temperature are observed. The anomalies in the dependence δ(1/B) _{T = const} are attributed to the fact that the quantizing magnetic field resonantly induces intersubband electron-electron interaction between the 2D electrons of the ground size-quantization subband and excited subband. The resonance fields B and the times corresponding to the collision-related broadening of the Landau levels are estimated. The concentration threshold of filling of the excited size-quantization subband is established at a level of n _s ≈ 8 × 10¹¹ cm^-2.