As[sub 2]S[sub 3]/Sr(Ti[sub 0.7]Co[sub 0.3])O[sub 3] and As[sub 2]S[sub 3]/Sr(Ti[sub 0.6]Fe[sub 0.4])O[sub 3] strip-loaded waveguides for integrated magneto-optical isolator applications

Abstract

Sr(Ti[sub 0.6]Fe[sub 0.4])O[sub 3] (STF) and Sr(Ti[sub 0.7]Co[sub 0.3])O[sub 3] (STC) room-temperature ferromagnetic oxides were grown epitaxially on LaAlO[sub 3](001), (LaSr)(AlTa)O[sub 3] (001) and Si (001) substrates. Both materials were demonstrated to be magneto-optically active, and more optically transparent at 1550nm wavelength compared with other non-garnet ferromagnetic materials. As[sub 2]S[sub 3]/STF and As[sub 2]S[sub 3]/STC strip-loaded waveguides were fabricated on epitaxial STF or STC films grown on LSAT (001) substrates using thermal evaporation and lift-off processing. The absorption of STF at 1550 nm was measured by ellipsometry and by optical transmission spectrum measurements of the As[sub 2]S[sub 3]/STF waveguides, which gave similar results. A novel design for a Non-Reciprocal Phase Shift (NRPS) strip-loaded waveguide using chalcogenide glass (ChG) as the guiding layer is proposed. The NRPS and figure of merit of these waveguides are simulated. The ChG strip-loaded waveguide structure shows advantages both in fabrication and device performance according to the simulation results. Our study suggests the possibility of magneto-optical magneto-optical isolators monolithically integrated on a silicon platform.