A switchable dual‐wavelength all‐fiber laser based on Panda‐type photosensitive polarization‐maintaining erbium‐doped fiber

Abstract

AbstractA novel swithcable dual‐wavelength fiber laser using Panda‐type photosensitive polarization‐maintaining erbium‐doped fiber (PMEDF) is proposed and experimentally demonstrated. Based on the integration of good photosensitivity and gain characteristics, two matched uniform fiber Bragg gratings (FBGs) are directly written in the PMEDF as reflectors, an all‐fiber linear laser cavity with no splice in it is then obtained. Because of the high birefringence of the PMEDF, both of the FBGs show two reflection peaks corresponding to two orthogonal linear polarization modes. By adjusting the polarization controller (PC) in the cavity, three lasing outputs (single‐wavelength at 1554.552 nm, single‐wavelength at 1554.916 nm, and dual‐wavelength at both wavelengths) are observed, respectively. The alternate wavelength switching is flexible. Repeated testing results show that a high‐quality lasing output with side‐mode suppression ratio (SMSR) better than 50dB is achieved in all switching cases, the peak power of the laser either in single‐wavelength output or in dual‐wavelength output keeps stable with a small fluctuation less than 0.46 dB. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 386–389, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24928