Magnetic-resonance study of the diluted magnetic semiconductor ${\mathrm{Pb}}_{1\mathrm{-}\mathit{x}\mathrm{-}\mathit{y}}$${\mathrm{Sn}}_{\mathit{y}}$${\mathrm{Mn}}_{\mathit{x}}$Te

Electron paramagnetic resonance (EPR) was investigated in samples of the magnetically diluted semiconductor ${\mathrm{Pb}}_{1\mathrm{-}\mathit{x}\mathrm{-}\mathit{y}}$ ${\mathrm{Sn}}_{\mathit{y}}$ ${\mathrm{Mn}}_{\mathit{x}}$Te in the temperature range T=1.3–100 K. The samples had compositions in the range x=0.005–0.06,y=0.12–0.72 and carrier concentrations between p=1.6×${10}^{19}$ and 1.4×${10}^{21}$ ${\mathrm{cm}}^{\mathrm{-}3}$. The temperature dependence of the EPR linewidth is strongly dependent on the carrier concentration. This can be understood within the framework of the Korringa relaxation mechanism and the two-valence-band model of magnetic properties of these crystals. For samples with high carrier concentrations (ferromagnetic at low temperatures) we obtained an s-d exchange integral of ${\mathit{J}}_{\mathit{s}\mathit{d}}$=33±2 meV. The role of metal vacancies in the effect of electron bottleneck of the EPR is also discussed.