https://doi.org/10.1051/epjap:2004184
Deep defect states in diluted magnetic semiconductors Pb1-x Snx Te:Yb
1
Physics Department of Moscow State University, Moscow 119992, Russia
2
Faculty of Material Science of Moscow State University, Moscow
199992, Russia
3
Institute of Material Science Problems, Chernovtsy 274001, Ukraine
Corresponding authors: skip@mig.phys.msu.ru zvereva@mig.phys.msu.ru
Received:
20
October
2003
Revised:
19
May
2004
Accepted:
25
June
2004
Published online:
30
August
2004
The galvanomagnetic effects in new diluted magnetic semiconductors
PbSnxTe:Yb were studied to build the energy level diagram under
variation of the alloy composition and establish the connection between the
parameters of electronic structure and magnetic properties. It was found
that the Hall coefficient increases almost by order of magnitude with
increasing the temperature. As tin content decreases, while the ytterbium
concentration grows, the hole concentration decreases by several times. The results are explained by assuming a formation of an
ytterbium-induced deep defect level in the energy spectrum of the alloys,
which moves up to the top of the valence band with increasing the ytterbium
concentration and pins the Fermi level within the valence band at
sufficiently high impurity content. The hole concentration vs. ytterbium
content dependence was used to calculate the energy position of the Fermi
level in the frame of two-band dispersion law and to determine the position
of Yb level in the alloys. The diagram of the charge carrier energy spectrum
under varying the alloy composition was built.
PACS: 71.28.+d – Narrow-band systems; intermediate-valence solids / 71.55.-i – Impurity and defect levels / 72.15.Gd – Galvanomagnetic and other magnetotransport effects
© EDP Sciences, 2005