Electron-gas cooling studied by measurements of noise temperature
Data from a detailed investigation of the variation of longitudinal and transverse noise temperature with changing electric field strength in compensated n-InSb(Cr) are presented. It is found that longitudinal noise temperature decreases with the diminishing electron concentration, n, and it does not exceed the lattice temperature TO, when n<2*1011 cm-3 at electric fields E<100 V cm-1. It has been explained that the existing electron-gas cooling effect in electric fields is mainly responsible for this decrease in the noise temperature. Investigation of the noise temperature in the transverse magnetic field and at different lattice temperatures supports the presence of the cooling effect. The influence of the fluctuating potential barriers of the conduction band edge on the noise temperature and electric conductivity are also discussed.