Sub-kHz-linewidth broadband-swept fiber laser based on Rayleigh scattering-enabled Brillouin random lasing oscillation with dynamic tunning Brillouin gain spectrum.

A sub-kHz-linewidth broadband-swept fiber laser using Rayleigh scattering-based Brillouin random lasing oscillation is proposed and experimentally demonstrated. Benefiting from Brillouin-involved acoustic damping and arbitrary-wavelength distributed Rayleigh feedback, leveraging instantaneously tuning Brillouin gain spectrum induced by a frequency-sweeping pump, a highly coherent random lasing emission with cavity mode elimination as well as frequency noise suppression is achieved in a sweeping manner. Results show that the proposed sweeping Stokes laser with a two-order-magnitude compressed linewidth of 840 Hz and 20 dB frequency noise suppression can unprecedentedly operate over the maximum wavelength range of 16 nm.

Observation and all-optical manipulation of replica symmetry breaking dynamics in a multi-Stokes-involved Brillouin random fiber laser photonic system.

In this paper, we propose and demonstrate an all-optical control of RSB transition in a multi-wavelength Brillouin random fiber laser (MWBRFL). Multi-order Stokes light components can be subsequently generated by increasing the power of the Erbium-doped fiber amplifier (EDFA) inside the MWBRFL, providing additional disorder as well as multiple Stokes-involved interplay. It essentially allows diversified laser mode landscapes with adjustable average mode lifetime and random mode density of the 1 order Stokes, which benefits the switching between replica symmetry breaking (RSB) and replica symmetry (RS) states in an optically controlled manner.