Origin of transition metal clustering tendencies in GaAs based dilute magnetic semiconductors

Abstract

While isovalent doping of GaAs (e.g. by In) leads to a repulsion between the solute atoms, two Cr, Mn, or Fe atoms in GaAs are found to have lower energy than the well-separated pair, and hence attract each other. The strong bonding interaction between levels with t2 symmetry on the transition metal (TM) atoms results in these atoms exhibiting a strong tendency to cluster. Using first-principles calculations, we show that this attraction is maximal for Cr, Mn and Fe while it is minimal for V. The difference is attributed to the symmetry of the highest occupied levels. While the intention is to find possible choices of spintronic materials that show a reduced tendency to cluster, one finds that the conditions that minimize clustering tendencies also minimize the stabilization of the magnetic state.

arXiv commentTo appear in Appl. Phys. Lett

References in corpus (7)

• Ferromagnetic semiconductors
• Unconventional carrier-mediated ferromagnetism above room temperature in ion-implanted (Ga, Mn)P:C
• First-principles investigation of the assumptions underlying Model-Hamiltonian approaches to ferromagnetism of 3d impurities in III-V semiconductors
• Ferromagnetism in Mn doped GaAs due to substitutional-interstitial complexes
• Disorder effects in diluted magnetic semiconductors
• Ferromagnetism in Mn-doped GaN: From Clusters to Crystals
• Single-Band Model for Diluted Magnetic Semiconductors: Dynamical and Transport Properties and Relevance of Clustered States

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