Interaction of low-density 2DEG with acoustic phonons

The energy relaxation of two-dimensional electron gas (2DEG) with low densi ty (2.2x10(10) cm(-2)) in selectively-doped In0.53Ga0.47As/InP heterostruct ures has been studied over a range of electron temperatures 0.1 < T-e < 2 K . The Joule power of the de current was employed for heating the electron g as. with the four terminal ac resistance of the sample used as electron the rmometer. We found that the interaction with a screened small-angle piezoel ectric potential of the acoustic phonons dominates in the temperature range 0.1 < T-e < 0.4 K. At higher temperatures 0.5 < T-e < 1.5 K, the change of energy balance equation is associated with a gradual transition from the s mall-angle interaction to a quasi-elastic one. The screening of the electro n-phonon interaction and the deformation potential of acoustic phonons must be taken into consideration in this temperature range. The best fit to the data was obtained with piezoelectric constant h(14) = (0.95 +/-0.05)x 10(7 ) Vcm(-1) and deformation potential E-D = (6+/-1) eV for both temperature r anges.