Critical temperatures of the two-band model for diluted magnetic semiconductors

  title={Critical temperatures of the two-band model for diluted magnetic semiconductors},
  author={Florentin Popescu and Yucel Yildirim and Gonzalo Alvarez and Adriana Moreo and Elbio Dagotto},
  journal={Physical Review B},
Using dynamical mean field theory and Monte Carlo simulations, we study the ferromagnetic transition temperature (T{sub c}) of a two-band model for diluted magnetic semiconductors (DMS), varying coupling constants, hopping parameters, and carrier densities. We found that T{sub c} is optimized at all fillings p when both impurity bands fully overlap in the same energy range, namely when the exchange couplings J and bandwidths are identical. The optimal T{sub c} is found to be about twice larger… Expand

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