Widely Tunable Narrow-Linewidth Lasers Using Self-Injection DBR Lasers

A widely tunable distributed Bragg reflector (DBR) laser with kilohertz linewidth output is demonstrated using a dual-loop self-injection scheme. The self-injection-locked narrow linewidth DBR laser can be tuned by 13 nm, covering 18 channels, with side mode suppression ratios over 38 dB and linewidths all <;10 kHz.