Theoretical analysis of nth-order cascaded continuous-wave Raman fiber lasers I Model and resolution

Abstract

We develop an approximate analytical solution to the steady-state equations that describe a nested fiber, Raman laser cavity that incorporates Bragg reflectors. From this solution the output power, the threshold power, and the efficiency are found. Numerical simulation of a six-step cascade shows that the approximate analytical solution is accurate within 1.5%. It appears that the laser behaves differently depending on whether it has an even or odd number of Stokes waves.