Phase Synchronization of Monolithic Dual DFB Lasers for Microwave Photonics: Experiment vs Model

International audience; The experimental implementation of optically carried RF signals, in the 1-100 GHz range and beyond, is fundamental for microwave photonics applications. The technique of heterodyning two laser waves provides an interesting alternative to direct modulation of light. Indeed, it allows generating directly a single-sideband signal over an optical carrier, that is inherently insensitive to dispersion in a fiber link. It also features a 100% modulation depth, a broad and continuous tunability. Phase-locking to electronic local oscillators results in optical beatings of very high spectral purity; furthermore, high microwave frequencies 100 GHz) can be reached by suitable multiplication or downconversion techniques (at the expense of a degradation of the phase noise performances)