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

Priya Mahadevan, J. M. Osorio-Guillen, Alex Zunger

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 pa…