Ultrasonic Attenuation in n-Type Ge. II. Effects of Uniaxial Stress

Abstract

The stress dependence of the ultrasonic attenuation α(X) in Sb doped Ge was measured at low temperatures over the wide concentration region 3.3×10¹⁵ to 1.6×10¹⁸ cm⁻³. In the intermediate concentration region the behavior of α(X) at low stresses is different from that observed in the low concentration region except the sample with 3.1×10¹⁶ Sb cm⁻³. A simple model is proposed which explains qualitatively the experiment in the lower part of the intermediate region. In the high concentration region a free electron gas model can explain the behavior of α(X) provided that the existence of a single relaxation time τ is assumed in this system. The values of τ estimated based on this model are consistent with those in the stress free case.