Effects of Uniaxial Stress and Magnetic Field on the Low-Temperature Thermal Conductivity of p -Type Ge and Si

Uniaxial stress dependence of the low-temperature thermal conductivity of lightly-doped p -type Ge and Si is calculated in detail by taking account of elastic and inelastic phonon scattering by holes bound to acceptor impurities. The stress modifies the temperature dependence as well as the magnitude of the thermal conductivity K ( T ). The most clearcut prediction is that K ( T ) of p -Si under the stress exhibits a dip as a function of temperature, which gives a direct evidence for the contribution of inelastic scattering to K ( T ). It is shown that a magnetic field also gives rise to a considerable change in K ( T ) of p -Si. In this connection, a brief discussion is given on the ultrasonic paramagnetic resonance of acceptor holes.