60-nm-thick basic photonic components and Bragg ... - OSA Publishing

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Abstract: We demonstrate integrated basic photonic components and Bragg gratings using 60-nm-thick silicon-on-insulator strip waveguides. The ultra-thin ...
60-nm-thick basic photonic components and Bragg gratings on the silicon-on-insulator platform Zhi Zou,1 Linjie Zhou,1,* Xinwan Li,1,2 and Jianping Chen1 1

State Key Laboratory of Advanced Optical Communication Systems and Networks, Department of Electronic Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China 2 University of Michigan and Shanghai Jiao Tong University Joint Institute, Shanghai, 200240, China * [email protected]

Abstract: We demonstrate integrated basic photonic components and Bragg gratings using 60-nm-thick silicon-on-insulator strip waveguides. The ultra-thin waveguides exhibit a propagation loss of 0.61 dB/cm and a bending loss of approximately 0.015 dB/180° with a 30 μm bending radius (including two straight-bend waveguide junctions). Basic structures based on the ultra-thin waveguides, including micro-ring resonators, 1 × 2 MMI couplers, and Mach-Zehnder interferometers are realized. Upon thinningdown, the waveguide effective refractive index is reduced, making the fabrication of Bragg gratings possible using the standard 248-nm deep ultra-violet (DUV) photolithography process. The Bragg grating exhibits a stopband width of 1 nm and an extinction ratio of 35 dB, which is practically applicable as an optical filter or a delay line. The transmission spectrum can be thermally tuned via an integrated resistive micro-heater formed by a heavily doped silicon slab beside the waveguide. ©2015 Optical Society of America OCIS codes: (130.3120) Integrated optics devices; (130.7408) Wavelength filtering devices; (230.7370) Waveguides; (350.2770) Gratings.

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#244025 (C) 2015 OSA

Received 1 Jul 2015; revised 27 Jul 2015; accepted 28 Jul 2015; published 30 Jul 2015 10 Aug 2015 | Vol. 23, No. 16 | DOI:10.1364/OE.23.020784 | OPTICS EXPRESS 20784

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1. Introduction Silicon photonic integration has been developing rapidly in recent years due to its large-scale integration capability and compatibility with complementary metal-oxide-semiconductor (CMOS) technologies. The typical thickness of strip silicon waveguides is around 200-500 nm [1]. Recently, ultra-thin waveguides with thickness