Calculation of nonreciprocal phase shift in magnetooptic waveguide with Si guiding layer

A nonreciprocal phase shift in a magnetooptic waveguide with a Si guiding layer is discussed. The magnetooptic waveguide was installed in an optical isolator employing the nonreciprocal phase shift. The magnetooptic waveguide had a magnetic garnet/Si/SiO₂ structure, which was realized by wafer bonding technique. The nonreciprocal phase shift in the magnetooptic waveguide with the Si guiding layer was calculated at a wavelength of 1.55 μm. A required thickness of the magnetic garnet cladding layer was obtained by calculating the nonreciprocal phase shift. An optical isolator employing the nonreciprocal phase shift, which could be operated under unidirectional magnetic field, was proposed by contriving the layer structures in the interferometer.