QUANTUM EFFECTS AND THE PHASE-DIAGRAM OF THE ELECTRONIC SYSTEM OF HIGHLY COMPENSATED SEMICONDUCTORS IN MAGNETIC-FIELD

The quantum effects in InSb conductivity have been studied near the me tal-insulator transition (MIT) of the percolation type caused by compe nsation. In highly compensated semiconductors parameters deviate from that predicted by the week localization and by the electron-electron i nteraction in disordered materials. The agreement can be achieved assu ming that only the volume of percolation cluster is available for cond ucting electrons. Surprising negative magnetoresistance with two minim a have been observed. The analysis of the phenomenon was performed on the base of the quantum correction theory and the model taking into ac count the Fermi energy increase due to Zeeman effect.