Fizika Nizkikh Temperatur: Volume 45, Number 2 (February 2019), p. 270-277 ( to contents , go back )
Low-temperature magnetic field dependences of spontaneous magnetization of low concentration (≤ 0.2 at.%) iron impurity electron system in mercury selenide crystal
T.E. Govorkova, V.I. Okulov, and K.A. Okulova
M.N. Mikheev Institute of Metal Physics, Ural Branch of the Russian Academy of Sciences Yekaterinburg 620108, Russia
Received November 19, 2018, published online December 20, 2018
There are presented the results of the experimental study and theoretical description of magnetic field dependences of mercury selenide single crystal magnetization with low ((0.01 ≤ 0.2) at.%) concentration of iron impurities at T = 5 K. Using detailed analysis of experimental data obtained one have been first derived the contributions of spontaneous magnetism of electron system of iron atom donor impurity hybridized states, having the shape of magnetization curves with saturation. For comparative consideration the like measurements were carried out on non-doped mercury selenide single crystal and on that with gallium impurities (0.05 аt.%) as well. The results obtained in so doing allowed us to confirm our development of the interpretation of experimental data. On the basis of previously developed theoretical ideas about electron systems under study there have been obtained formulas, describing magnetic field dependences of spontaneous magnetization. By fitting the theoretical results to the experimental ones the parameters, characterizing spontaneous spin magnetism of impurity systems, have been determined. It turned out that the given parameters are in good agreement also with experimental data, obtained in studying the anomalies of the Hall effect and the temperature dependences of magnetic susceptibility in the same systems.
Key words: transition element impurities in semiconductors, hy-bridized electron states, low-temperature magnetism, spontaneous magnetization of electrons.