EFFECT OF COMPRESSIVE UNIAXIAL STRESS ON HIGH FIELD DOMAINS IN n‐TYPE Ge

The effect of compressive uniaxial stress on the threshold field for nucleation of high field domains in n‐type Ge at 27°K has been measured. The increase in threshold field is approximately quadratic in stress and is about 15% for a stress of 104 kg/cm2 applied along a 〈100〉 direction parallel to the current and about 37% for a stress of 104 kg/cm2 applied along a 〈100〉 perpendicular to the current. These results indicate that, while in a strong electric field the 〈110〉 valleys are occupied at high stresses, transfer of electrons to these valleys is not the cause of bulk negative differential conductivity in n‐type Ge.