Switchable Dual-wavelength Fiber Ring Laser Research Articles

Compact Dynamic In-Fiber Acoustically-Induced Mach-Zehnder Interferometer Based on Phase Mismatch and Its Application in a Tunable and Switchable Dual-Wavelength Laser

A compact and robust in-fiber acoustically-induced Mach-Zehnder interferometer (AI-MZI) was demonstrated based on the phase mismatch in an acoustic wave driving fiber Bragg grating (FBG). The fiber structure of the AI-MZI was easy to fabricate and of a uniform diameter with larger refractive index difference in its arm part, which helped to reduce the length of the arm. In the experiment, the total length of the AI-MZI was less than 7 cm and the response time was about 120 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\mu$</tex-math></inline-formula> s. The bandpass isolation and resonant center wavelength could be optimized by changing the power and frequency of the radio frequency source, respectively. As its application, a tunable and individually switchable dual-wavelength fiber ring laser was realized and characterized. The proposed structure gains advantages of robustness, easy fabrication, compact size and fast tuning speed accordingly. At the same time, it provides another practical way to use an FBG to introduce phase mismatch into an acousto-optic fiber grating.

Switchable dual-wavelength fiber ring laser featuring twin-core photonic crystal fiber-based filter

A simple configuration for the generation of a switchable dual-wavelength fiber ring laser is presented. The proposed configuration employs a short twin-core photonic crystal fiber acting as a Mach-Zehnder interferometer at room temperature. A polarization controller is further utilized to enable switchable dualwavelength operation.