THE ELECTRON LOCALIZATION BY MAGNETIC-FIELD IN N-INSB

The detailed experimental investigation is performed for the conduction tensor of n-InSb single crystals in the wide range of concentration 1.5.10(15)-1.5.10(16) cm-3 and the magnetic field values up to 72 kOe at the helium temperature region. The experimental behaviors of sigma parallel-to infinity H-alpha and sigma perpendicular-to infinity H-beta where alpha reduces from 3 to 2.3 under the concentration growth and beta increases from 1 to 2 and more at the beginning of the ultra-quantum limit (UQL) region are observed. Then magnitude beta decrease with increasing H. It is shown that the quantum screening (QS) region occupies a significant part in the UQL region. The longitudinal and transverse diffusion is considered theoretically for the UQL region within the one-electron model applied before for the case of the classical screening (CS) and involved with the quasi one-dimensional character of the electron dynamics and ability of the Anderson electron localization in the random potential of charged impurities distributed chaotically. Unlike the CS region where sigma parallel-to infinity H-6 and sigma perpendicular-to infinity H8/3 it is shown that these dependences should be significantly different, namely, sigma parallel-to infinity H-2 and sigma perpendicular-to infinity H0. The theoretical results agree to some extent with the experimental dependence in the CS region and quite disagree in the quantum region. The possible reasons for the observed differences are discussed.