Feedback effects of mirror loss in /spl lambda//8 phase-shifted DFB-LDs

Feedback effects of mirror loss (FEML) in DFB-LDs were demonstrated for the first time. By changing the phase-shift in DFB-LDs, we controlled successfully the lasing wavelength deviation from the Bragg wavelength. The Bragg deviation dependence of the FEML was clarified theoretically and experimentally. The reduced relative intensity noise in /spl lambda//8 phase-shifted DFB-LDs under external optical feedback proved that negative FEML could make the DFB-LDs more stable and insensitive to external fluctuations.