Generation of nonequilibrium phonons and phonon-electron drag in bismuth

The direct flux of the nonequilibrium phonons emitted by charge carriers in crossed electric and magnetic fields under their supersonic drift in a high quality bismuth single crystal was observed directly for the first time. Special geometry of the experiment made it possible to measure a signal of the acoustomagnetoelectric effect signal which is resulted from the drag of charge carriers by nonequilibrium phonons. Measurement of the acoustomagnetoelectric signal magnitude allowed us to determine which part of the electric power fed to the sample is transformated to an acoustic power