Electronic structure and x-ray magnetic circular dichroism in (Ge,Mn)Te diluted magnetic semiconductors

Abstract

The electronic structure of the (Ge,Mn)Te diluted magnetic semiconductors was investigated theoretically from first principles, using the fully relativistic Dirac linear muffin-tin orbital (LMTO) band structure method. The electronic structure is obtained with the local spin-density approximation (LSDA) as well as the LSDA+U method. The x-ray magnetic circular dichroism (XMCD) spectra of (Ge,Mn)Te DMSs at the Mn L 2,3 edges are investigated theoretically from first principles. The origin of the XMCD spectra in the compound is examined. The calculated results are compared with available experimental data.

First principle electronic structure calculations of ternary alloys Hg1−xMnxTe in zinc-blende structure

“…Because of the exchange interaction between the carriers and the magnetic impurities, bulk DMS have interesting magnetic and magneto-optical properties [1,2]. The signature characteristic of DMS is the carrier-mediated ferromagnetic exchange with which magnetic and electronic properties of microelectronic devices can be linked [3].…”

New insights into defects and magnetic interactions inducing lattice disordering in Co2Fe0.5Cr0.5Al

“…It can be seen that in Co 2 FeAl subjected to quenching, there is an increase in the value of non-magnetic fraction accompanied by about 5% of the Fe atoms experiencing hyperne elds much lower than that of the defect free sites. This implies that these are due to Fe atoms associated with A 2 type of disordering as has been reported [31][32][33][34][35][36][37][38][39][40][41][42][43][44]. Based on the comparison of the MS results as obtained in the as melted and…”

“…This implies that these are due to Fe atoms associated with A 2 type of disordering as has been reported. 31–44 Based on the comparison of the MS results as obtained in the as melted and quenched Co 2 Fe 0.8 Cr 0.2 Al it could be deduced that there are no appreciable changes in the hyperfine parameters associated with Fe atoms subsequent to quenching treatment. This might imply that the Co 2 FeAl substituted with 20% of Cr atoms remains almost robust against an increase in the lattice disordering due to quenching effects.…”

“…Due to enhanced A 2 type of disordering ne Cr rich zones are primarily formed at the grain boundaries in the ferromagnetic matrix. Magnetic ordering temperature for Cr rich Fe-Cr has been reported to be close to 673 K. [38][39][40] Hence annealing at a temperature close to 673 K is expected to result in reduction of Fe-Cr repulsion mediated by spin frustration due to AFM interaction between Fe and Cr atoms. This is understood to result in the enhancement of magnetically ordered zones with the partial dissolution of Cr rich zones.…”

First-Principles Study of the Structural, Electronic, Magnetic and Thermal Properties of the Cr Doped Ge6Mn2Te8 and Ge6Fe2Te8 Systems

“…Due to the exchange interaction between the carriers and the magnetic impurities, the bulk DMS have interesting magnetic and magneto-optical properties [1,2]. The signature characteristic of the DMS is the carrier-mediated ferromagnetic exchange where the magnetic and electronic properties of the microelectronic devices can be linked [3]. Transition metal doped II-VI and III-V diluted magnetic semiconductors have many unique magneto-optical, magneto-electrical and * corresponding author; e-mail: khenata_rabah@yahoo.fr magneto-transport properties that are essential for the future generation of the spintronic device applications [4].…”