Numerical investigation on the spectral and temporal characteristics of amplified spontaneous emission in chirped pulse regenerative amplifiers

Accurate characterization of the amplified spontaneous emission (ASE) is greatly important for designing a high-contrast chirped pulse amplifier (CPA). In this paper, we develop a theoretical model based on small signal gain calculation (SSGC) to simulate the temporal and spectral profiles of the ASE output power of a chirped pulse regenerative amplifier. Also, the finite difference time domain (FDTD) is utilized as a robust mathematical method to describe ASE characteristics. Comparison of the two methods introduces the developed SSGC as a fast, greatly efficient and accurate technique to predict and analyze the ASE behavior in a CPA system.