Narrow-linewidth tunable lasers with retro-reflective external cavity

• Main Authors: Wang, Ning, Feng, Ming, Feng, Zhiqing, Lam, Man Ying, Gao, Lei, Chen, Bo, Liu, A. Q., Tsang, Yuen Hong, Zhang, Xuming
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2013
• Subjects: DRNTU::Engineering::Electrical and electronic engineering
• Online Access: https://hdl.handle.net/10356/102730; http://hdl.handle.net/10220/16420
• Institution: Nanyang Technological University

This letter presents the development of a fiber-pigtailed narrow-linewidth tunable laser that utilizes a retro-reflective optical system to construct the external cavity. For wavelength selection, a fixed etalon is employed to provide the International Telecommunication Union (ITU) grid with the 50-GHz spacing and a lead zirconate titanate-actuated tunable filter to select one ITU mode to resonate. The laser device measures a linewidth of 7 kHz, an output power of 14 dBm, a sidemode suppression ratio (SMSR) 55 dB, a tuning range 40 nm, and a response speed ~2 ms. The superior performance well demonstrates the advantages of external cavity construction for the narrow-linewidth tunable lasers and may find applications in the emerging digital coherent communications.