Magnetic Anisotropy of Ion-Implanted (100), (110) Garnet Films

Anisotropy changes caused by He⁺ and H2⁺ implantations in (100), (110), and (111) magnetic garnet films have been studied. In (100) films, in striking contrast to (111) films, uniaxial anisotropy field changes were almost the same for He⁺ and H2⁺ implantations. In (110) films, the orthorhombic anisotropy parameter B changed greatly with H2⁺ implantations, consistent with anisotropy changes in (111) films. The change in parameter A for He⁺-implanted (110) films was of the same order as for H2⁺ implantations. Magnetocrystalline anisotropy K1 in H2⁺ implanted films was determined from the angular dependence of (100) in-plane resonance fields. The sign of K1 changed to positive with H2⁺ implantation. It was found that H2⁺ implantations have a great effect on ¿111 and K1, but have little influence on ¿100.