Tunable multi-wavelength all-fiber Raman source using fiber Sagnac loop filter

Effect of Rayleigh-scattering distributed feedback on multiwavelength Raman fiber laser generation

“…Several techniques have been proposed to ensure stable multi-wavelength laser operation based on semiconductor optical amplifiers 1 , erbium-doped fiber lasers 2 , spectrum sliced supercontinuum 3 or Raman fiber lasers (RFLs) [4][5][6][7][8][9][10] .…”

“…Different types of multiwavelength RFLs, mainly in ring cavity configurations, have been proposed and demonstrated utilizing multi-channel filters based on Fabry-Perot 4-6 or Sagnac 7 interferometers. As a result, multi-wavelength RFLs can emit up to 58 stable lines simultaneously with 100 or 50 GHz spacing 4 in different spectral bands 7 . Fiber Bragg gratings (FBGs) reflecting several wavelengths being either multimode 8 , phase-shifted 9 or sampled 10 have also been demonstrated for multi-wavelength operation in RFLs with linear cavities but, generally with a relatively low number of spectral lines.…”

“…Note that all multiwavelength RFL schemes [4][5][6][7][8][9][10] are based on long fibers (4-50 km), so Rayleigh scattering (RS) accumulated over a long distance and amplified via the Raman effect, may play an important role in such systems. A stable narrow-linewidth lasing utilising RS-based random distributed feedback only (without any regular reflector) has been demonstrated recently 13 .…”

Tunable Fibre Lasers Based on Optical Amplifiers and an Opto-VLSI Processor

“…Zhang et al, 2009). The PMF-based fiber loop mirror filters can provide various functionalities like both the peak wavelength tunability and FSR tunability, which can be controlled by adjusting the effective length and birefringence of multiple PMF segments depending on the relative phase difference between two orthogonal polarization modes within the loop (Kim et al, 2003;Z. Y. Liu et al, 2008).…”

“…Bellemare et al, 2000;X. M. Liu et al, 2005b), SOAs (Pleros et al, 2002), and schemes based on stimulated Raman scattering (SRS) gain (Kim et al, 2003) and stimulated Brillouin scattering (SBS) gain (Nasir et al, 2009). In addition, hybrid gain mechanisms using a combination of the above mechanisms have also been used (Han et al, 2005).…”