QUANTUM OSCILLATIONS OF RESISTANCE AND MAGNETIZATION IN THE DEGENERATE SEMICONDUCTOR N-HGCR2SE4

In the magnetic field range Delta H = 8-60 kOe we observed and studied the anomalous oscillations in the magnetic field dependence of the re sistance and magnetization of single crystals of n-HgCr2Se4. The absen ce of periodicity in 1/H in the Delta H = 8-20 kOe range can be explai ned by the non-Fermi-liquid behavior of the electron subsystem and agr ees with the theory of the de Haas-van Alphen in systems with intermed iate valence. In stronger fields, Delta H = 20-60 kOe, the amplitude o f the fundamental harmonic decreases, with the number and amplitude of the higher-order harmonics increasing, As a result, noise is superimp osed on the signal as magnetic field strength grows. The temperature d ependence of the magnetization is the sum of the monotonic spin-wave c ontribution and the oscillating part. (C) 1998 American Institute of P hysics. [S1063-7761(98)02205-7].