Room-Temperature Ferromagnetism in a II-VI Diluted Magnetic SemiconductorZn1−xCrxTe

The magnetic and magneto-optical properties of a Cr-doped II-VI semiconductor ZnTe were investigated. Magnetic circular dichroism measurements showed a strong interaction between the $sp$ carriers and localized $d$ spins, indicating that ${\mathrm{Z}\mathrm{n}}_{1-x}{\mathrm{C}\mathrm{r}}_x\mathrm{T}\mathrm{e}$ is a diluted magnetic semiconductor. The Curie temperature of the film with $x=0.20$ was estimated to be $300\pm 10\mathrm{K}$, which is the highest value ever reported for a diluted magnetic semiconductor in which $sp\mathrm{\text{−}}d$ interactions were confirmed. In spite of its high Curie temperature, ${\mathrm{Z}\mathrm{n}}_{1-x}{\mathrm{C}\mathrm{r}}_x\mathrm{T}\mathrm{e}$ film shows semiconducting electrical transport properties.