Second (1178 nm) and third (1242 nm) Stokes Raman fiber lasers without intermediate Stokes cavities

Abstract

We report and propose a simple Raman fiber laser scheme that generates two or three order Raman Stokes components by using a single strong (unidirectional) cavity formed by a high-reflecting fiber Bragg grating and air-glass interface (fiber output); the intermediate cavities are non-grating, weak and bi-directional cavities that serve as 'virtual links' or energy reservoirs. Once the strong cavity reaches operation, it practically consumes (converts) all the energy from pump and intermediate components into a single and clamped (unidirectional) signal. For example, the use of second-Stokes fiber Bragg grating together with glass-air output operated and harvested practically all the energy. Analogously, third Stokes emission was obtained by changing the grating and hence relying on first and second non-grating formed intermediate cavities. The system uses commercial silica fiber and minimizes the use of lossy and costly fiber Bragg gratings. This proposal broadens the possibilities for covering the entire 1000-2000 nm window for applications that use silica fibers.

Design of 1178 nm diode laser with step waveguide layers for reduced voltage and low vertical divergence

“…However, yellow diode lasers are not easily realized due to the limited active materials. Currently, several approaches including frequency doubling of solid-state lasers, sum-frequency generation of solid-state lasers, and frequency doubling of fiber lasers have been investigated [5][6][7][8][9][10]. Unfortunately, these approaches need complex systems and have low efficiencies.…”