PHONON-INDUCED DRAG OF CHARGE-CARRIERS IN HETEROSTRUCTURES IN MAGNETIC-FIELDS - LIMIT OF WEAK FIELDS

The response of a 2D gas of charge carriers of mobility mu in magnetic field B to pulsed phonon beams is considered. Previously we derived a quantum Langevin equation for the centre-of-mass of the carrier gas, which allows us to calculate the time integrated drag current. This fo rmula is studied in the weak magnetic field limit. When the ratio of t he cyclotron frequency omega(c) to the frequency omega of phonons is s mall and mu B much less than 1, the general formula coincides with the corresponding expression obtained in the frame of the Boltzmann equat ion with the collision integral independent of B.