Tunable Raman fiber laser induced by Rayleigh back-scattering in an ultra-long cavity

Abstract

We report an ultra-long Raman laser with a 46 km fiber length that behaved as a Rayleigh back-scattering-based optical feedback. The laser was tunable from 1550 nm to 1571 nm (3 dB bandwidth) with the insertion of an optical grating filter. Evaluations on the spectral evolution and power development were also performed from the results obtained. In fact, it was discovered that the spectral broadening effect between the modeless spectra resembled the same process that happens in a typical fiber cavity that has high reflectors at each cavity end. In addition, the output power showed a square-root development with respect to the input power.

Lyot-filter-based multiwavelength random distributed feedback fiber laser

“…31, 32 A number of different random DFB fiber laser configurations are realized up to date. [32][33][34][35][36][37][38] In particular, random DFB fiber lasers can be multiwavelength, 35-37 tunable, 38,39 can operate in different spectral bands [40][41][42] and provide cascaded operation at higher Stokes components. 40,42 Multiwavelength generation in the RDFB-FL has been demonstrated earlier in the RDFB-FL by employing discrete fiber bragg gratings.…”

NLSE-based model of a random distributed feedback fiber laser

“…The gain is provided by a stimulated Raman scattering. Up to date, a number of different random DFB fiber lasers schemes is realized [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] . Namely, random fibre lasers can operate in different spectral bands 3,4 , be cascaded, i.e.…”

“…Namely, random fibre lasers can operate in different spectral bands 3,4 , be cascaded, i.e. emit higher order Stokes waves [3][4][5] , the laser can be easily tunable 13,14 , provides multi-wavelength output 6,10,12 . The noise level of random DFB fiber lasers could be lower than of conventional lasers 18 making them attractive for telecom applications.…”

Modeling of the spectrum in a random distributed feedback fiber laser within the power balance modes

“…Up to date, a number of different schemes of random DFB fiber lasers were demonstrated [11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26] . Namely, random DFB fiber lasers can operate in different spectral bands 12,13 , emit higher order Stokes waves [12][13][14] , be tunable 22,23 and multiwavelength 15,19,21 .…”

“…Namely, random DFB fiber lasers can operate in different spectral bands 12,13 , emit higher order Stokes waves [12][13][14] , be tunable 22,23 and multiwavelength 15,19,21 . The noise level of random DFB fiber lasers could be lower than of conventional lasers 27 making them attractive for telecom applications.…”