Improvement of the wavelength switching behavior of semiconductor tunable lasers through optical feedback from a periodic reference filter based on a novel prism-based implementation of a Fox-Smith resonator

We show that the wavelength switching behavior of semiconductor tunable lasers can be improved through optical feedback from a stable reference filter. The filter is based on a novel prism-based implementation of a Fox-Smith resonator and has a response consisting of periodically spaced peaks, both in reflection and transmission. The improvement of the wavelength switching behavior stems from the suppression of the thermally induced wavelength drift associated with the switching of the tuning currents.