Transmitted acoustic phonon drag between parallel two-dimensional electron gases: Monte Carlo simulation
We present Monte Carlo (MC) simulation of transmitted acoustic phonon (TAP) drag between barrier-separated two-dimensional (2D) electron gases in the AlGaAs/GaAs system. Non-equilibrium acoustic phonons emitted by the hot 2D electron gas in the biased GaAs channel travel across the sample. These phonons are partially absorbed in an unbiased 2D channel where they induce a drag current. Simulation includes 2D electron-non-equilibrium acoustic phonon interaction for both deformation-potential and piezoelectric coupling. Non-equilibrium phonon distribution is calculated numerically. TAP drag is simulated at 4.2 K in a multiple quantum well containing equivalent high-mobility 2D electron gases. Drift velocities around 1000 m s-1 are found in the drag channel (2D gas without outer field), when it is driven by TAP drag from a large number (10-50) of 2D electron gases subjected to electric field of 1000 V m-1 TAP drag is mainly due to the deformation-potential coupling.