The Study Of All-fiber Superfluorescent Source Operating Near 980 Nm

The superfluorescent fiber source operating near 980 nm is a fiber source that uses amplified spontaneous emission?ASE?process in rare earth doped fiber to obtain a broad spectrum output.It has application prospects in high-brightness pump sources and new light sources.In this paper,the theoretical and experimental study on the 980 nm superfluorescent source is carried out.The design scheme of 980 nm superfluorescent source based on distributed side-coupling cladding pump?DSCCP?fiber is proposed and realized all-fiber high power 980 nm band superfluorescent source output based on DSCCP fiber.The main work of the thesis is as follows:1.Based on the Yb³⁺ions energy level structure and spectral characteristics,a preliminary theoretical analysis of the 980 nm superfluorescent source is carried out,and the necessary conditions for the realization of the superfluorescent source in the 980nm band are given.2.Experimental study on all-fiber 980 nm band superfluorescent sourceBased on the 60/125-125 micron DSCCP fiber,the superfluorescent source operating near 980 nm was designed and built,which verified the feasibility of the 980nm superfluorescent source and realized the all-fiber structure.And for the first time in the world,the superfluorescent output of the 980 nm band with a power of 8.38 W was obtained.On this basis,the output power of the 980 nm superfluorescent source was increased to 17.1 W,and the slope efficiency reached 14.6%.This is the maximum power output of the 980 nm band superfluorescent source.3.Theoretical study and numerical simulation of 980 nm superfluorescent source based on DSCCP fiber.Based on the steady-state rate equation model of DSCCP fiber structure,a simple and effective numerical criterion for parasitic laser oscillation threshold is proposed for the parasitic laser oscillation phenomenon that limits power boost.Using this numerical criterion,The power expansion capability of superfluorescent source operating near 980nm is explored which reveals the influence of the end-feedback and pumping light coupling coefficient on the power expansion capability of the light source.