Low Temperature Physics: 37, 210 (2011); https://doi.org/10.1063/1.3573664 (10 pages)
Fizika Nizkikh Temperatur: Volume 37, Number 3 (March 2011), p. 269-280    ( to contents , go back )

Electronic structure of chromium-doped lead telluride-based diluted magnetic semiconductors

E.P. Skipetrov, N.A. Pichugin

The Moscow State University М.В. Lomonosov , Moscow, 119992, Russia
E-mail: skip@mig.phys.msu.ru

E.I. Slyn'ko, and V.E. Slyn'ko

Институт проблем материаловедения им. И.Н. Францевича НАН Украины ул. Вильде, 5, г. Черновцы, 58001, Украина
pos Анотація:

Received September 24, 2010

Abstract

The crystal structure, composition, galvanomagnetic and oscillatory properties of the Pb1–xySnxCryTe (x = 0, 0.05–0.30, y ≤ 0.01) alloys have been investigated with varying matrix composition and chromium impurity concentration. It is shown that the chromium impurity atoms dissolve in the crystal lattice at least up to 1 mol.%. The following increase of the chromium concentration leads to the appearance of microscopic regions enriched with chromium and inclusions of Cr–Te compounds. A decrease of the hole concentration, a pn-conversion of the conductivity type and a pinning of the Fermi level by the chromium resonant level are observed with increasing chromium content. Initial rates of changes in the free carrier concentration on doping are determined. The dependences of electron concentration and Fermi level on tin content are calculated by the two-band Kane dispersion relation. A diagram of electronic structure rearrangement for the chromium-doped alloys with varying the matrix composition is proposed.

PACS: 71.20.Nr Semiconductor compounds;
PACS: 71.55.–i Impurity and defect levels;
PACS: 72.20.My Galvanomagnetic and other magnetotransport effects;
PACS: 75.50.Pp Magnetic semiconductors.

Key words: chromium impurity, galvanomagnetic effects, Shubnikov-de Haas oscillations, deep chromium level, electronic structure.

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