Quantum Oscillations in the Phonon Scattering by a 2-DEG of a Si-MOSFET

Abstract

Phonon scattering by a 2-DEG has been studied using ballistic heat pulses. Heat pulses generated by a gold thin-film resistance heater have been detected by a CdS bolometer after passing through a 2-DEG in the inversion layer of a Si-MOSFET held at 4.2K. The detected ballistic phonon pulses have been examined as a function of gate voltage and applied magnetic field. At a magnetic field of 5T the pulse height oscillates with an amplitude of about 0.5% of the initial pulse height and with a period which is identical to the period of Shubnikov-de Haas oscillations in electrical conductivity.