Electron Paramagnetic Resonance in the Narrow-Gap Semiconductor Pb0.996Cu0.003MnxGdyS: Effects of Interaction between Mn2+ and Gd3+ Ions with the Participation of Free Charge Carriers

The electron paramagnetic resonance spectra of Mn2+ and Gd3+ ions in crystals of the narrow-gap semiconductor Pb0.996Cu0.003MnxGdyS (x $$ \approx $$ 6 × 10–4, y $$ \approx $$ 4 × 10–4) were discovered to demonstrate an unusually strong dependence of the spin relaxation processes of these ions on temperature and power of X-band microwave radiation acting on the crystal sample in a magnetic field. The observed effect manifests itself as sharp dependences of the line shape parameters of the EPR spectra of Mn2+ and Gd3 ions on temperature and microwave power. The results of the experimental study indicate a high efficiency of the exchange interaction between these ions via free charge carriers.