Double spacing multi-wavelength L-band Brillouin erbium fiber laser with Raman pump

Abstract

A new multi-wavelength Brillouin erbium fiber laser (BEFL), which operates in the L-band region with double frequency Brillouin spacing, is demonstrated. This design uses a Raman pump (RP) and a piece of 2 km highly nonlinear fiber as a gain medium. The double frequency spacing is achieved by employing a dual ring configuration, which is formed by utilizing a four-port circulator that removes the odd-order Stoke signals. Twenty Stokes and seventeen anti-Stokes lines, which have optical signal to noise ratio (OSNR) greater than 15 dB, are generated simultaneously with a spacing of 0.16 nm when Brillouin pump and RP powers were fixed at the optimum values of 8 dBm and 40 mW, respectively. The BEFL can be tuned in the range between 1591 nm to 1618 nm. The proposed configuration increases the number of lines generated and the OSNR, and thus allows a compact multi-wavelength laser source to be realized.

Multi-wavelength Brillouin–Raman fiber laser generation assisted by multiple four-wave mixing processes in a ring cavity

“…From figures 4(a) and (b), it is also confirmed that by increasing the pump power, other Stokes lines can also be generated as long as the threshold power is exceeded. Since there is no reflection of the BP and the even Stokes lines in the backward direction, the optical signal-to-noise ratio (OSNR) is also improved in the backward direction as compared to the values that have been reported in previous works [16][17][18][19]. http://iopscience.iop.org/1555-6611/23/7/075108/article…”

“…A disadvantage of the MBFL is that the channel spacing, which is typically 0.08 nm (~10 GHz), is extremely hard to de-multiplex, thus rendering the MBFL unsuitable for practical applications. In order to address this problem, research has now explored the development of MBFLs with channel spacings that approximate double Brillouin shifts using two ring cavities [16][17][18][19].…”