Magnetic anisotropy in ilmenite-hematite solid solution thin films grown by pulsed laser ablation

Ferromagnetic thin films of the ilmenite-hematite solid solution Fe_2-xTi_xO₃ with x=0.6 and x=0.8 have been grown on (0 0 1) sapphire substrates. X-ray diffraction analysis reveals that the films are single phase with the ilmenite (R over(3, -)) crystal structure. Strong easy-plane anisotropy is observed for the two films, which are nominally n or p type with K₁=-8×10⁶ J m^-3 for x=0.6 and -11×10⁶ J m^-3 for x=0.8 at T=4 K. The trigonal splitting of the ⁵T_2g energy level of Fe²⁺ is inferred to be 0.11 eV, and the zero-field splitting parameter D to be equal to 15 K.