Charge carrier mobility in n-CdxHg1-xTe crystals subjected to dynamic ultrasonic stressing

The Hall mobility was studied in the n-CdxHg1-xTe crystals subjected to dyn amic ultrasonic stressing (W-US less than or equal to 10(4) W/m(2), f = 5-7 MHz). It was found that, in field of the ultrasonic deformation, an increa se in the carrier mobility in the impurity conduction region (T < 120 K) an d a decrease in the intrinsic conduction region (T > 120 K) occurred in all tested samples. In this case, the magnitude of the sonic-stimulated variat ion in mu(H) increases with decreasing structural perfection of a crystal. Different mechanisms of ultrasonic influence on mu(H) with regard to scatte ring by optical phonons, ionized impurities, and alloy potential are analyz ed, with the current flow conditions in the crystal taken into account. It is shown that, in the impurity conduction region, the main cause of the son ic-stimulated increase of the Hall mobility is the smoothing of the macrosc opic intracrystalline potential that results from the inhomogeneity of the crystals. In the intrinsic conduction region, a decrease in mobility is cau sed by an increase in the intensity of scattering by the optical phonons. ( C) 2000 MAIK "Nauka/Interperiodica".