Thermoelectric Cyclotron Resonance in Germanium

Abstract

A novel method for observing cyclotron resonance in semiconductors has been predicted and observed. The measured parameter is a dc thermoelectric current generated by carriers which are heated by means of cyclotron resonance absorption in a spatially varying electromagnetic field. Measurements are reported for n- and p-type Ge at 4°K and 70 GHz. The thermoelectric current at resonance is found roughly to be proportional to the logarithm of the microwave power. The line shape also depends on power and, at power levels approaching the values for impact ionization, displays certain peculiarities. The power dependence of conductivity modulation by cyclotron absorption is also reported.