Nanometric control of an ultrafast passively mode-locked quantum-well laser at 1070 nm by optical self-feedback

Ultrafast mode-locked semiconductor lasers are compact and energy-efficient photonic sources that are employed in communication applications at wavelengths of 1310 nm and 1550 nm. Novel semiconductor lasers emitting at 1070 nm may open new telecommunication windows [Yamamoto et al., Opt. Express 16, 19836 (2008)]. The impact of external optical self-feedback with nanometric precision on the pulsed emission of a passively mode-locked quantum-well semiconductor laser emitting at 1070 nm is experimentally studied. The free-running repetition rate amounts to 13.6 GHz and optical pulses shorter than 10 ps are generated. Wavelength scale dynamics in the output power, the spectral and temporal domain are experimentally demonstrated and explained in view on recent theoretical studies proposing sub-micrometer emission effects.