Ferromagnetism in nitrogen-doped cubic ZrO2: Density-functional investigations

Stable ferromagnetism in nitrogen-doped cubic ZrO2 is reported based on first-principles calculations. A substitution of oxygen by nitrogen introduces spin-polarized 2p states near the Fermi level, producing a total magnetic moment of 1.0 μB. The hole-mediated direct 2p–2p interaction and indirect 2p–4p/4d–2p interaction result in a long-range ferromagnetic ground state. With large magnetization energy, room temperature ferromagnetism is expected. Additionally, the Zr-rich condition with NO as N source is suggested to realize the N doping in cubic ZrO2.