Selective-area growth of magnetic garnet crystals by liquid-phase epitaxy and its application to waveguide devices

Magnetic garnet layers with the composition of (LuNdBi)₃(FeAl)₅O₁₂ have been grown on (111)-oriented Gd₃Ga₅O₁₂ (GGG) substrates, which are patterned with stripes of different widths using a Ti mask, by liquid-phase epitaxy to fabricate one-step grown magnetic garnet waveguides. The garnet layers were investigated by scanning electron microscopy, X-ray diffraction measurements, energy-dispersive X-ray analysis and reflection high-energy electron diffraction. The layers grown on Ti-masked regions had a coarse and uneven surface, which is attributed to the damage in the surface of GGG substrates during the growth. The waveguiding experiment indicated that the light waves could be guided within the waveguide with a propagation loss of approximately 0.7 dB/mm.