Study on backward stimulated Raman scattering in HC-PCF

In order to produce high intensity backward stimulated Raman scattering light (BSRS), the backscattered Raman scattering and amplification characteristics of hydrogen (H2) in double Raman cell were studied. Both Raman cells are filled with high-pressure hydrogen. The front Raman cell is used to generate seed light, and the rear Raman cell is used to amplify seed light. The stimulated Raman scattering (SRS) of BSRS seeds with different structures of hollow core photonic crystal fiber (HC-PCF), pump energy and H2 pressure were measured in Raman cell 1. The experimental results show that in Aifo structure, BSRs signal appears the earliest, and the quantum conversion is as high as 65%. When the pump energy exceeds 70uj, the BSRs intensity is approximately saturated when the H2 pressure is 4MPa. Finally, the BSRS seed light is amplified by Raman cell 2, and up to 500 times energy amplification can be obtained.