Diluted magnetic semiconductors with correlated impurities: Mean-field theory with RKKY interaction

Theoretical investigations of spin polaron in a quantum dot in the "spin doping" superlattice systems Cd 1 - X in Mn X in Te/Cd 1 - X out Mn X out Te are presented. We estimated the donor ionization energy by variational technique and the spin polaronic shift using the mean field theory with modified Brillouin function. Our results show that significant enhancement of donor ionization energy and spin polaronic shift occur in a dot when compared to a quantum well, wire and bulk systems.

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Investigation on Mo-doped SnO2 for potential use in magnetoelectronic applications: The DFT framework

International Journal of Modern Physics B ◽

10.1142/s0217979220500204 ◽

2020 ◽

Vol 34 (05) ◽

pp. 2050020

Author(s):

Younes Ziat ◽

Maryama Hammi ◽

Zakaryaa Zarhri ◽

Charaf Laghlimi ◽

Rachid Bouachraoui ◽

...

Keyword(s):

Density Functional ◽

Diluted Magnetic Semiconductors ◽

Magnetic Semiconductors ◽

Mean Field ◽

Field Approximation ◽

Mean Field Approximation ◽

Present System ◽

The Density Functional Theory ◽

Spin Polarized ◽

Diluted Magnetic

The goal of this paper is to study the effect of the small amount of molybdenum-doped [Formula: see text] on the magnetism behavior of that system. We utilized the density functional theory (DFT): DFT framework within MACHIKANEYAMA2002V09 package based on Coherent Potential Approximation (CPA). Inducing the magnetism in the diluted magnetic semiconductors (DMS) with a low dopant concentration at adequate room-temperature is a challenge, so, we restricted the Mo impurity at 2%. In addition, the small amount of Mo-doped [Formula: see text] is found optimal in many studies related to other fields. The ferromagnetic stability is observed in [Formula: see text] system, since the [Formula: see text] state of Mo element is found around the Fermi level and is 100% spin polarized, the half-metallic characteristic is useful in magnetoelectronic applications. Within the mean-field approximation (MFA) we predict the Curie temperature, as an obtained value, the [Formula: see text] K, consequently, the present system showed potential promise for real applications.

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Spin Polarization and Exchange Interaction in a Diluted Magnetic Qunautm Dot

Advances in Condensed Matter Physics ◽

10.1155/2009/561201 ◽

2009 ◽

Vol 2009 ◽

pp. 1-7 ◽

Cited By ~ 2

Author(s):

A. John Peter ◽

K. Lily Mary Eucharista

Keyword(s):

Field Theory ◽

Quantum Dot ◽

Spin Polarization ◽

Ionization Energy ◽

Mean Field Theory ◽

Mean Field ◽

Binding Energies ◽

Spin Interaction ◽

Itinerant Electron ◽

Diluted Magnetic

The spin interaction energy of differentMn2+ions with and without an itinerant electron is evaluated for different dot radii. Magnetization is calculated for various concentrations ofMn2+ions with different dot sizes. Spin polaronic shifts are estimated using a mean field theory. The lowest binding energies of electrons in aCd1-xMnxTequantum dot are also calculated. Results are obtained forCd1−xinMnxinTe/Cd1−xoutMnxoutTestructures as a function of the dot radius variationally. It is found that (i) more number ofMn2+spins enhance the spin polaronic effect and it varies linearly with the concentration, (ii) spin polarization ofMn2+ions increases with the concentration for any dot radii, (iii) the magnetization of Mn subsystem increases with the concentration ofMn2+ions and this feature is predominant for smaller dots, and (iv) variation of increase in ionization energy is sharper for smaller dots with increase in concentration. These results are discussed with the available data in literature.

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Phase Diagram of a Model for Diluted Magnetic Semiconductors Beyond Mean-Field Approximations

Physical Review Letters ◽

10.1103/physrevlett.89.277202 ◽

2002 ◽

Vol 89 (27) ◽

Cited By ~ 77

Author(s):

Gonzalo Alvarez ◽

Matthias Mayr ◽

Elbio Dagotto

Keyword(s):

Phase Diagram ◽

Diluted Magnetic Semiconductors ◽

Magnetic Semiconductors ◽

Mean Field ◽

Diluted Magnetic ◽

Mean Field Approximations

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Effects of clustering and dimensionality on the magnetic properties of diluted magnetic semiconductors

MRS Proceedings ◽

10.1557/proc-794-t8.8 ◽

2003 ◽

Vol 794 ◽

Author(s):

R. N. Bhatt ◽

Malcolm. P. Kennett ◽

Adel Kassaian

Keyword(s):

Magnetic Properties ◽

Transition Temperature ◽

Diluted Magnetic Semiconductors ◽

Magnetic Semiconductors ◽

Mean Field ◽

Impurity Band ◽

Growth Conditions ◽

Band Model ◽

Ferromagnetic Transition ◽

Diluted Magnetic

ABSTRACTThe magnetic properties of films of diluted magnetic semiconductors (DMS) such as (Ga,Mn)As, as well as bulk grown crystals of similar materials, have been found to be extremely sensitive to growth conditions, both in terms of the ferromagnetic transition temperature, and the details of their magnetization curves. We study an impurity band model for carriers in Mn-doped DMS applicable in the low carrier density regime, and discuss the effects of clustering on the magnetic properties of DMS, using both numerical mean field and Monte Carlo simulations. In addition, we study the effects of dimensionality on the transition temperature and other magnetic behaviour, and compare our results with experimental data.

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