Pressure Dependence of Hole-Mn and Mn-Mn Exchange Interactions in C${\mathrm{d}}_{0.95}$M${\mathrm{n}}_{0.05}$Se

Magnetophotoluminescence due to the A exciton has been studied in a diluted magnetic semiconductor C${\mathrm{d}}_{0.95}$M${\mathrm{n}}_{0.05}$Se under hydrostatic pressures of 0–2 GPa at 1.4 K. The experimental data on the pressure dependencies of the hole-Mn $p-d$ and Mn-Mn $d-d$ exchange interactions suggest that in concurrence with an increase in the $p-d$ transfer integral the on-site Coulomb energy U and $p-d$ charge-transfer energy $\Delta$ decrease with increasing pressure. The deduced value, $d\ln U/dP=-2.5\mathrm{}\times {10}^{-2\mathrm{}}{\mathrm{GPa}}^{-1\mathrm{}}$, of the relative pressure coefficient of U is about 4 times in magnitude as great as the linear compressibility of lattice.