Low-threshold Stimulated Raman Scattering Based on Liquid-filled Hollow-core Photonic Crystal Fiber

To study the application of microstructure optical fiber in optofluidic technology, the HC-PCF with carbon tetrachloride ( CCl4 ) was filled and pumped with a 1 064 nm pulsed laser to generate the stimulated Raman scattering. By collapsing the cladding holes, CCl4 can be filled only in the core of the 1. 8 m long, 10μm core diameter HC-PCF by capillary forces and external pressures. The light is guided by total internal reflection since the effective refractive index of cladding air holes ( about 1. 1 ) is lower than CCl4(about 1. 45). The 1 064 nm pump laser has a repetition rate of 200 kHz, a pulse width of 186 ps and a tunable output power of 0 ~1 W. Two orders of Stokes line are generated at 1 118 nm and 1 172. 3 nm. By adjusting the pump power, the corresponding peak power of first-order Raman threshold is 0. 94 kW. Results show that the microstructure optical fiber is a good carrier for optofluidic technology.