Electron paramagnetic resonance in Hg1-xMnxTe1-ySey

Electron paramagnetic resonance has been studied in diluted magnetic semiconductor Hg1-xMnxTe1-ySey with y=0.01 and x=0.01, 0.03, 0.05, 0.14 and with y=0.075, x=0.14 in the temperature range 20-290 K. It is found that the EPR linewidth increases with increasing manganese concentration, and decreases with increasing selenium content. From the high temperature linewidth dependence the paramagnetic Curie-Weiss temperature is estimated as \ theta \ = 10 K for the sample with x=0.01, y=0.01 and \ theta \ = 18 K for x=0.03, y=0.01. These values of theta together with those obtained in the magnetic susceptibility measurements give the nearest-neighbour exchange constant in Hg1-xMnxTe1-ySey with y=0.01, J(NN)/k(B)=-5.4 K. The calculated infinite temperature linewidths are considerably smaller than the extrapolated experimental values. We ascribe this effect to a coalescence of the Mn2+ ion six hyperfine lines into a single broad peak.Trends in Advanced Materials and Processes, 3rd Yugoslov-Materials-Research-Society Conference, Sep 20-24, 1999, Herceg Novi, Yugoslavi