Abstract

When considering quantum electronic transport phenomena, phonons have got a bad name for themselves for causing scattering/dephasing, etc. However, we have shown that coherent phonons (bulk acoustic waves) with frequencies up to about one terahertz can be used for controlled high-speed manipulation of electronic transport, with potential applications in microwave electronics and detectors for acoustic nanoscopy. The bulk acoustic waves are generated by femtosecond pulsed laser excitation of thin film transducers and interact with the electronic states in semiconductor nanostructures via the deformation potential coupling. We have previously demonstrated bulk acoustic wave-driven transport effects in Schottky and resonant tunneling devices and 2D electron systems. In this presentation, I will review some of our past results, leading up to our recent demonstration of using bulk acoustic waves to modulate, at high-speed, the THz emission from a quantum cascade laser.