The d‐d exchange interaction in the diluted magnetic semiconductor ZnFeS

We measured the magnetic susceptibility of Zn1−xFexS (x≤0.03) and found typical Curie–Weiss behavior above 100 K. Based on the high temperature expansion series developed for Fe based diluted magnetic semiconductors, we estimated the exchange interaction constant between the nearest neighbors JNN=−37 K, which is the largest value for Fe‐based diluted magnetic semiconductors studied so far.