Specific features of the temperature behavior of the ESR spectra of Fe-doped mercury selenide

摘要

The ESR study of a dilute magnetic semiconductor HgSe:Fe with the iron concentration 2 × 10~(18) cm~(-3) < N_(Fe) < 3 × 10~(19) cm~(-3) was carried out in the temperature range 77 K < T < 300 K. As was shown by microstructure analysis, the iron ions are distributed uniformly in the bulk of HgSe:Fe samples and do not form a crystal structure different from that of zinc blende in their vicinity. Based on the g-factor calculations it was concluded that Fe~(3+) ions in the tetrahedral sites of HgSe samples are the source of the ESR signal; the shape of the ESR spectra is determined by the combined effect of the Jahn-Teller distortions of the tetrahedral environment and the displacements of an iron ion from the center of the tetrahedron; the evolution of the ESR spectra with increasing the iron concentration can be explained within the model of the regular lattice of charged donors. The temperature at which the regular lattice of impurity ions is formed was determined by the maximum on the temperature dependence of the ESR linewidth for the samples with different iron concentrations.