Open AccessSagnac loop mirror and micro-ring based laser cavity for silicon-on-insulator
Author(s) -
Yi Zhang,
Shaoshi Yang,
Hang Guan,
Andy Eu-Jin Lim,
GuoQiang Lo,
Peter Magill,
Tom BaehrJones,
Michael Hochberg
Publication year - 2014
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.22.017872
Subject(s) - optics , laser linewidth , materials science , optoelectronics , laser , silicon on insulator , lasing threshold , silicon , wavelength , physics
An integrated laser is a key component in silicon based photonic integrated circuits. Beyond incorporating the gain medium, on-chip cavity design is critical to device performance and yield. Typical recent results involve cavities utilizing distributed Bragg gratings that require ultra-fine feature sizes. We propose to build laser cavity on silicon using a Sagnac loop mirror and a micro-ring wavelength filter for the first time. The Sagnac loop mirror provides broadband reflection, which is simple to fabricate, has an accurately-controlled reflectivity, and negligible excess loss. Single-mode operation is achieved with the intra-cavity micro-ring filter and, using a 248 nm stepper, the laser wavelength can be lithographically controlled within a standard deviation of 3.6 nm. We demonstrate a proof-of-concept device lasing at 1551.7 nm, with 44 dB SMSR, 1.2 MHz linewidth and 4.8 mW on-chip output power.