Title

Coherent stokes Raman spectroscopy of conduction electron spin flip transitions in Cd1-xFexTe: A Van Vleck paramagnet

Published in:

Physical Review B 78,4 ( 2008 )

Abstract

The conduction-band spin splitting in Cd1-xFexTe bulk crystals is delineated on the basis of the Raman transitions manifested in coherent Stokes Raman scattering (CSRS). The independence at low temperatures and absence of saturation at high magnetic fields displayed by the Raman shift are characteristic of Van Vleck paramagnetism of Fe2+ interacting with s-like conduction electrons via the s-d exchange interaction. The exchange constant (N-0 alpha) deduced from these experiments is (255 +/- 10)meV. When Fe2+ concentration (x) exceeds similar to 0.002 the intrinsic negative g-factor of electrons in CdTe is compensated by the positive s-d exchange interaction. The separation of the first magnetic excited state Gamma(4) lying just above the nonmagnetic Gamma(1) ground state, deduced from the analysis of the spin splitting as a function of temperature, is 16 +/- 2 cm(-1).

Date of this Version

January 2008