Ferromagnetic semiconducting behavior of Mn1−xCrxTe compounds

The magnetic and electrical transport properties of ferromagnetic semiconductor ${\mathrm{Mn}}_{1\ensuremath{-}x}{\mathrm{Cr}}_{x}\mathrm{Te}$ ($x=0.04$, 0.08, and 0.14) compounds have been investigated. These compounds have ferromagnetic behavior with hysteresis loops showing a coercivity of $300--985\phantom{\rule{0.3em}{0ex}}\mathrm{Oe}$ at $5\phantom{\rule{0.3em}{0ex}}\mathrm{K}$. The hysteresis loop is observed even at room temperature for ${\mathrm{Mn}}_{0.86}{\mathrm{Cr}}_{0.14}\mathrm{Te}$. The substitution of Cr for Mn leads to a change from an antiferromagnetic state of MnTe to a ferromagnetic (or ferrimagnetic) state of ${\mathrm{Mn}}_{1\ensuremath{-}x}{\mathrm{Cr}}_{x}\mathrm{Te}$. Moreover, the incorporation of Cr into the host antiferromagnetic semiconductor MnTe lattice is confirmed by the structural characterization, which proves further that the ferromagnetic properties are not a result of the secondary phase. The typical feature of the thermally activated conduction processes for semiconductors has been verified by electrical property measurement.