Magnetic Garnet Thick Films Deposited with Aerosol Deposition Method for Optical Isolator

Bismuth-substituted yttrium iron garnet (Bi:YIG, Bi0.5Y2.5Fe5O12) films have been deposited with aerosol deposition method. We investigated the deposition rate, crystallinity, magnetic and optical properties dependent on carrier gas flow rate (0.5 L/min ∼ 8 L/min) and annealing temperature. With increasing annealing temperature, the crystallinity of Bi:YIG film was improved and the saturation magnetization increased to reach to 1.1 kG at 800°C. The magneto-optical effect, Faraday rotation, increased to 1.4 deg/μm by annealing at 700°C around the wavelength of 0.5 μm. The optical transmittance of the Bi:YIG film was also improved in visible region.