Ferromagnetism in Diluted Magnetic Semiconductors Pb1-x-yGexCryTe
Magnetic and galvanomagnetic properties of Pb1-x-yGexCryTe (x=0.02-0.20, y=0.01-0.08) solid solutions have been investigated. It was found that the magnetic susceptibility of these alloys contains two contributions: a paramagnetic Curie-Weiss share (T<50 K) due to the paramagnetism of Cr3+ ions and a high temperature ferromagnetic share (T<300 K). Dependence of the concentration of paramagnetic centers on the composition of the matrix was obtained. The magnetic field dependences of the Hall coefficient in the vicinity of the metal-insulator transition were measured and the main parameters of charge carriers in terms of the two-band conduction model were estimated. The experimental results are discussed in the framework of the electronic structure model, assuming varying electrical and magnetic activities of Cr ions as function of germanium content in the alloys.
E.P. Skipetrov et al., "Ferromagnetism in Diluted Magnetic Semiconductors Pb1-x-yGexCryTe", Solid State Phenomena, Vols. 152-153, pp. 295-298, 2009