Linewidth narrowing and stabilization from a short cavity ring laser source design for fibre sensor applications

A Brillouin ring laser source intended for distributed optical fiber sensing is detailed, showing high maximum output (1.5 mW), a strong linewidth narrowing effect for both the pump and the output, reaching 10 kHz linewidth and noise reduction (RIN ~ -145 dB/Hz), resulting in a high performance BRL source that can provide both pump and probe signals for BOTDA applications.