Non-reciprocal photonic devices, including optical isolators and circulators, are indispensible components in optical communication systems. However, the integration of such devices on semiconductor platforms has been challenging because of material incompatibilities between semiconductors and magneto-optical materials that necessitate wafer bonding, and because of the large footprint of isolator designs. Here, we report the first monolithically integrated magneto-optical isolator on silicon. Using a non-reciprocal optical resonator on an silicon-on-insulator substrate, we demonstrate unidirectional optical transmission with an isolation ratio up to 19.5 dB near the 1,550 nm telecommunication wavelength in a homogeneous external magnetic field. Our device has a small footprint that is 290 µm in length, significantly smaller than a conventional integrated optical isolator on a single crystal garnet substrate. This monolithically integrated non-reciprocal optical resonator may serve as a fundamental building block in a variety of ultracompact silicon photonic devices including optical isolators and circulators, enabling future low-cost, large-scale integration.
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Yu, Z. & Fan, S. Complete optical isolation created by indirect interband photonic transitions. Nature Photon. 3, 91–94 (2009).
Dötsch, H. et al. Applications of magneto-optical waveguides in integrated optics: review. J. Opt. Soc. Am. B 22, 240–253 (2005).
Sung, S., Qi, X. & Stadler B. J. H. Integrating yttrium iron garnet onto nongarnet substrates with faster deposition rates and high reliability. Appl. Phys. Lett. 87, 121111 (2005).
Boudiar, T. et al. Magneto-optical properties of yttrium iron garnet (YIG) thin films elaborated by radio frequency sputtering. J. Magn. Magn. Mater. 284, 77–85 (2004).
Shintaku, T. Integrated optical isolator based on efficient nonreciprocal radiation mode conversion. Appl. Phys. Lett. 73, 1946–1948 (1998).
Fujita, J., Levy, M., Osgood, R. M. Jr, Wilkens, L. & Dötsch, H. Waveguide optical isolator based on Mach–Zehnder interferometer. Appl. Phys. Lett. 76, 2158–2160 (2000).
Kim, H. S., Bi, L., Dionne, G. F. & Ross, C. A. Magnetic and magneto-optical properties of Fe-doped SrTiO3 films. Appl. Phys. Lett. 93, 092506 (2008).
Bi, L., Kim, H. S., Dionne, G. F. & Ross, C. A. Structure, magnetic properties and magnetoelastic anisotropy in epitaxial Sr(Ti1–xCox)O3 films. New J. Phys. 12, 043044 (2010).
Zaman, T. R., Guo, X. & Ram, R. J. Semiconductor waveguide isolators. J. Lightwave Technol. 26, 291–301 (2008).
Wang, Z. & Fan, S. Optical circulators in two-dimensional magneto-optical photonic crystals. Opt. Lett. 30, 1989–1991 (2005).
Kono, N., Kakihara, K., Saitoh, K. & Koshiba, M. Nonreciprocal microresonators for the miniaturization of optical waveguide isolators. Opt. Express 15, 7737–7751 (2007).
Jalas, D., Petrov, A., Krause, M., Hampe, J. & Eich, M. Resonance splitting in gyrotropic ring resonators. Opt. Lett. 35, 3438–3440 (2010).
Shoji, Y., Mizumoto, T., Yokoi, H., Hsieh, I. & Osgood, R. M. Magneto-optical isolator with silicon waveguides fabricated by direct bonding. Appl. Phys. Lett. 92, 071117 (2008).
Tien, M., Mizumoto, T., Pintus, P., Kromer, H. & Bowers, J. E. Silicon ring isolators with bonded nonreciprocal magneto-optical garnets. Opt. Express 19, 11740–11745 (2011)
Bi, L. Magneto-Optical Oxide Thin Films and Integrated Nonreciprocal Photonic Devices. PhD thesis, Massachusetts Institute of Technology (2011).
Bi, L., Hu, J., Dionne, G. F., Kimerling, L. & Ross, C. A. Monolithic integration of chalcogenide glass/iron garnet waveguides and resonators for on-chip nonreciprocal photonic devices. Proc. SPIE 7941, 794105 (2011).
Espinola, R. L., Izuhara, T., Tsai, M., Osgood, R. M. & Dötsch, H. Magneto-optical nonreciprocal phase shift in garnet/silicon-on-insulator waveguides. Opt. Lett. 29, 941–943 (2004).
Duan, G. H., Favre, H. & Le Guen, D. FM noise and linewidth reduction in a 1.5 µm InGaAsP DFB laser coupled to an external fiber resonator. Opt. Commun. 15, 111–114 (1988).
Henry, C. H. Theory of the linewidth of semiconductor lasers. IEEE J. Quantum Electron. 18, 259–264 (1982).
Hu, J. Planar Chalcogenide Glass Materials and Devices. PhD thesis, Massachusetts Institute of Technology (2009).
Integrated Optics Software FIMMWAVE 4.5, Photon Design, Oxford, UK; available at http://www.photond.com
Higuchi, S., Furukawa, Y., Tekekawa, S., Kamada, O. & Kitamura K. Magneto-optical properties of cerium-substituted yttrium iron garnet single crystals grown by traveling solvent floating zone method. Jpn J. Appl. Phys. 38, 4122–4126 (1999).
Gomi, M., Furuyama, H. & Abe, M. Strong magneto-optical enhancement in highly Ce-substituted iron garnet films prepared by sputtering. J. Appl. Phys. 70, 7065–7067 (1991).
Holzwarth, C. W., Barwicz, T. & Smith, H. I. Optimization of hydrogen silsesquioxane for photonic applications. J. Vac. Sci. Technol. B 25, 2658–2661 (2007).
The authors thank Jie Sun for discussions on silicon resonator fabrication. The support of the National Science Foundation and an Intel Fellowship for Lei Bi is gratefully acknowledged.
The authors declare no competing financial interests.
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Bi, L., Hu, J., Jiang, P. et al. On-chip optical isolation in monolithically integrated non-reciprocal optical resonators. Nature Photon 5, 758–762 (2011). https://doi.org/10.1038/nphoton.2011.270
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