From Event: SPIE OPTO, 2019
INVITED PRESENTATION
Distributed feedback (DFB) fiber Bragg grating (FBG) Raman fiber lasers (RFL) were first analysed by Perlin and Winful [1], predicting that meter long uniform FBGs could be used as a Raman oscillator to generate any wavelength with several 10’s watts of pump power. Pi phase shifted distributed feedback grating structures improved the characteristics of the laser significantly [2]. These Raman fiber lasers have improved over the years with a threshold of below 1W. Our own work resulted in several demonstrations of single frequency RFLs and random Raman fiber lasers (rRFL) up to 1 meter long, as well as the lowest reported threshold of 350mW for a RFL. This has been possible only by painstaking analysis and correction of the poor quality of FBGs. The slope efficiency of these lasers, however, is well below that predicted, limited by nonlinear optical effects. This paper will present the state-of-the-art in ultra-long FBGs needed for compact Raman fiber lasers, demonstrate some novel solutions and discuss the limiting issues remaining for improving performance.
References:
1. V. E. Perlin and H. G. Winful, "Distributed feedback fiber Raman laser," IEEE Journal of Quantum Electronics 37, 38-47 (2001).
2. Y. Hu and N. G. R. Broderick, "Improved design of a DFB Raman fibre laser," Optics Communications 282, 3356-3359 (2009).
© (2019) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Raman Kashyap, "Perfecting ultra-long fiber Bragg gratings for compact Raman lasers (Conference Presentation)," Proc. SPIE 10922, Smart Photonic and Optoelectronic Integrated Circuits XXI, 1092202 (Presented at SPIE OPTO: February 02, 2019; Published: 4 March 2019); https://doi.org/10.1117/12.2510016.6009829060001.