Magnetostriction constants of epitaxial La,Ga: YIG films measured by microwave resonance

The magnetostriction constants of Y_2.85La_0.15Fe_3.75Ga_1.25O₁₂ epilayers have been measured by observing the shift of the resonance line of a thin film which is stressed by three-point bending. The result is λ₁₁₁=−(0.75±0.15) × 10⁻⁶ and λ₁₀₀=−(0.4±0.1) × 10⁻⁶ which is in agreement with the measurements on bulk single crystals. This result indicates that there is no growth induced contribution to the magnetostriction in thin films of this garnet grown by liquid phase epitaxy.