Pressure Dependence of Hole-Mn and Mn-Mn Exchange Interactions in Cd0.95Mn0.05Se.

Abstract

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 $p\ensuremath{-}d$ and Mn-Mn $d\ensuremath{-}d$ exchange interactions suggest that in concurrence with an increase in the $p\ensuremath{-}d$ transfer integral the on-site Coulomb energy U and $p\ensuremath{-}d$ charge-transfer energy $\ensuremath{\Delta}$ decrease with increasing pressure. The deduced value, $d\mathrm{ln}U/dP\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}\ensuremath{-}2.5\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}2}{\mathrm{GPa}}^{\ensuremath{-}1}$, of the relative pressure coefficient of U is about 4 times in magnitude as great as the linear compressibility of lattice.