Ferromagnetic Cr_xTi_(1－x)N solid solution nitride thin films grown by pulsed laser deposition and their magnetoresistance

摘要

Epitaxial nitride films of Cr_xTi_(1－x)N were grown on MgO (001) by pulsed laser deposition under nitrogen radical irradiation, and their magnetic and transport properties were investigated, which was motivated by calculations on magnetism pointing out similarities of CrN to LaMnO_3, the parent compound of colossal magnetoresistance oxides. The films showed ferromagnetism for 0.28 ≤ x ≤ 0.5 and the T_c showed a maximum (140 K) at x =0.5. When x exceeded 0.5(x=0.58) ferromagnetism disappeared completely. At x=0.5, the nitride film showed a large magnetoresistance (6%-7% at 5 T), which had a maximum at 130 K.