Hydrostatic pressure influence on TC in (Ga,Mn)As

The influence of hydrostatic pressure on the Curie temperature ${T}_{C}$ of thin ferromagnetic (Ga,Mn)As layers is studied. New experimental data unambiguously point to both positive and negative pressure-induced changes of Curie temperature. The positive pressure coefficient is observed for samples with relatively high values of ${T}_{C}$ and can be quantitatively described by the $p\text{\ensuremath{-}}d$ Zener model of carrier-mediated ferromagnetism within the six-band $k\ifmmode\cdot\else\textperiodcentered\fi{}p$ formalism and the ab initio approach. First-principles calculations of structural, electronic, and magnetic properties of (Ga,Mn)As show that antiferromagnetic coupling of substitutional Mn atoms with interstitial ones may account for a decrease of ${T}_{C}$ under pressure in samples having a substantial concentration of interstitial Mn.