Europium nitride: a novel diluted magnetic semiconductor

Phys Rev Lett. 2013 Oct 18;111(16):167206. doi: 10.1103/PhysRevLett.111.167206. Epub 2013 Oct 18.

Abstract

Europium nitride is semiconducting and contains nonmagnetic Eu3+, but substoichiometric EuN has Eu in a mix of 2+ and 3+ charge states. We show that at Eu2+ concentrations near 15%-20% EuN is ferromagnetic with a Curie temperature as high as 120 K. The Eu3+ polarization follows that of the Eu2+, confirming that the ferromagnetism is intrinsic to the EuN which is, thus, a novel diluted magnetic semiconductor. Transport measurements shed light on the likely exchange mechanisms.