Compensation, interstitial defects and ferromagnetism in diluted semiconductors

Abstract

We present a quantitative theory for ferromagnetism in diluted III-V ferromagnetic semi-conductors in the presence of the two types of defects commonly supposed to be responsible for compensation: As anti-sites and Mn interstitials. In each case we reduce the description to that of an effective random Heisenberg model with exchange integrals between active magnetic impurities provided by ab initio calculation. The effective magnetic Hamiltonian is then solved by a semi-analytical method (locally self-consistent RPA), where disorder is treated exactly. Measured Curie temperatures are shown to be inconsistent with the hypothesis that As anti-sites provide the dominant mechanism for compensation. In contrast, if we assume that Mn interstitials are the main source for compensation, we obtain a very good agreement between the calculated Curie temperature and the measured values, in both as-grown and annealed samples.

References in corpus (11)

• Mn Interstitial Diffusion in (Ga,Mn)As
• Effects of annealing time on defect-controlled ferromagnetism in Ga1-xMnxAs
• High Curie temperature GaMnAs obtained by resistance-monitored annealing
• Calculating the Curie Temperature reliably in diluted III-V ferromagnetic semiconductors
• Influence of defects on the lattice constant of GaMnAs
• Determination of the local concentrations of Mn interstitials and antisite defects in GaMnAs
• Annealing-Dependent Magnetic Depth Profile in Ga[1-x]Mn[x]As
• Interstitial Mn in (Ga,Mn)As: Binding energy and exchange coupling
• RPA-CPA theory for magnetism in disordered Heisenberg binary systems with long range exchange integrals
• Origin of room temperature ferromagnetism in homogeneous (In,Mn)As thin films
• Effects of Capping on the (Ga,Mn)As Magnetic Depth Profile

Cited by in corpus (25)

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• Controlling Curie temperature in (Ga,Ms)As through location of the Fermi level within the impurity band
• Magnetism without magnetic impurities in oxides ZrO2 and TiO2
• Why RKKY exchange integrals are inappropriate to describe ferromagnetism in diluted magnetic semiconductors
• Magnetic spin excitations in diluted ferromagnetic systems: the case of $G{a}_{1-x}M{n}_{x}As$
• Non-perturbative $J_{pd}$ model and ferromagnetism in dilute magnets
• Unified picture for diluted magnetic semiconductors
• Ferromagnetism and impurity band in a new magnetic semiconductor: InMnP
• Precise tuning of the Curie temperature of (Ga,Mn)As-based magnetic semiconductors by hole compensation: Support for valence-band ferromagnetism
• Influence of the microstructure on the magnetism of Co-doped ZnO thin films
• Ferromagnetism and infrared electrodynamics of Ga${}_{1-x}$Mn${}_x$As}
• Magnetic and chemical nonuniformity in Ga[1-x]Mn[x]As films as probed by polarized neutron and x-ray reflectometry
• Superexchange induced canted ferromagnetism in dilute magnets
• Dynamical properties of a three-dimensional diluted Heisenberg model
• Relation of Curie temperature and conductivity: (Ga,Mn)As alloy as a case study
• Carrier induced ferromagnetism in the insulating Mn doped III-V semiconductor InP
• Optical conductivity of Mn doped GaAs
• Reconsidering the possibility of room temperature ferromagnetism in Mn doped Zirconium oxide
• Lifetimes of Magnons in Two-Dimensional Diluted Ferromagnetic Systems
• Comment on the PRL "Large-Scale Monte Carlo Study of a Realistic Lattice Model for Ga_(1-x)Mn_xAs"
• On the reliability of recent Monte Carlo studies of dilute systems of localized spins interacting with itinerant carriers
• Comparison between ab-initio and phenomenological modeling of the exchange couplings in diluted magnetic semiconductors: the case of $Z{n}_{1-x}C{r}_{x}Te$
• Magnetic properties of nanosized diluted magnetic semiconductors with band splitting