Narrow-linewidth self-injection locking 1 µm laser using a fiber Fabry–Perot resonator

The fiber resonator, with low loss, large mode volume, and excellent environmental resistance, is beneficial for realizing narrow-linewidth lasers using the self-injection locking method. This study demonstrates a narrow-linewidth 1 µm laser through self-injection locking of an electrically pumped diode laser to a high-Q fiber Fabry–Perot resonator. The locked laser exhibits a linewidth of less than 250 Hz, representing a significant reduction compared to the unlocked diode laser. Furthermore, by adjusting the operating current of the diode laser, the output wavelength of the locked laser can be tuned from 1036 to 1063 nm. This research provides a cost-effective, miniaturized, and easy-to-use solution for narrow-linewidth laser applications.