Observation of acoustic phonon Stokes and anti-Stokes peaks due to assisted tunnelling in a triple barrier structure

We present the first data on the change in tunnel current in a triple barri er resonant tunnelling diode (TBRTD) due to a pulse of nonequilibrium acous tic phonons. The change in current as a function of voltage Delta I(V) maps out two satellite peaks which occur either side of the first resonant volt age. The satellite peak which occurs at a lower voltage than the first reso nance is attributed to assisted tunnelling from the emitter to the lowest b ound state in the wells via acoustic phonon absorption. The peak which occu rs at a higher bias voltage than the first resonance is attributed to assis ted tunnelling via stimulated phonon emission from the emitter level to the lowest bound state in the quantum wells. (C) 1999 Elsevier Science B.V. Al l rights reserved.