Direct generation of all-fiber GHz burst-mode laser with flexible temporal tunability

GHz burst-mode lasers can offer critical support for many frontier applications. Unfortunately, at present, the generation of all-fiber GHz burst-mode lasers is extremely dependent on external modulation, thus requiring multistage fiber pre-amplifiers to compensate for great power attenuation. Here we demonstrate a simple and efficient method, which actively establishes the combined operation of controllable Q-switching and GHz harmonic mode-locking by performing burst-rectangular intensity modulation in all-fiber polarization-maintaining ring cavity, to directly generate all-fiber GHz burst-mode lasers with flexible temporal tunability. Each burst envelope can contain thousands of sub-pulses with about 17-ps width and 2.35169-GHz repetition rate. More than 20-mW average output power can be achieved with only 400-mW pump power. © 2024 Elsevier Ltd