Magnetic susceptibility and exchange in IV-VI compound diluted magnetic semiconductors

摘要: Magnetic susceptibility has been measured in ${\mathrm{Pb}}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$${\mathrm{Mn}}_{\mathrm{x}}$Te, ${\mathrm{Pb}}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$${\mathrm{Mn}}_{\mathrm{x}}$Se, and ${\mathrm{Pb}}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$${\mathrm{Gd}}_{\mathrm{x}}$Te with values of x from 0 to 0.08. The followed the Curie-Weiss behavior a small paramagnetic Curie temperature that indicated weak antiferromagnetic exchange coupling between magnetic ions. We analyze our results together previously published data for ${\mathrm{Pb}}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$${\mathrm{Mn}}_{\mathrm{x}}$S ${\mathrm{Pb}}_{1\mathrm{\ensuremath{-}}\mathrm{x}}$${\mathrm{Eu}}_{\mathrm{x}}$Te present review parameters IV-VI compound diluted semiconductors. find constants obtained high-temperature semiconductors are generally an order magnitude lower than those II-VI This fact can be explained by assuming superexchange is dominant mechanism all investigated systems. Within this we estimate taking into account crystalline electronic structure Our estimations agree experimental predict large difference