Compact all-fiber gas Raman light source based on hydrogen-filled hollow-core photonic crystal fiber pumped with single-mode Q-switched fiber laser

• A compact all-fiber gas Raman light source is reported.
• The gas Raman cell is based on hydrogen-filled hollow-core photonic crystal fiber.
• A single-mode Q-switched fiber laser is used as the Raman pump source.
• The Stokes pulse is much narrower than the pump pulse.
• The Stokes pulse duration and conversion efficiency were studied.

We report a compact all-fiber gas Raman light source based on hydrogen-filled HC-PCF gas cell with a SM Q-switched fiber laser as the Raman pump source. Theoretical model of the hydrogen SRS based on HC-PCF pumped with Q-switched fiber laser is also analyzed. Simulated results show that the Stokes pulse is much narrower than the pump pulse, and both the Stokes pulse duration and conversion efficiency are increased with the pump pulse energy of the same duration pump pulses. The experimental results are in agreement with the theoretical results in change trend. For the 120 ns pump pulses with the repetition rate of 5 kHz, the threshold pump energy and conversion efficiency at the threshold are 1.146 μJ and 2.69%.