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Acta Physica Sinica

Effect of laser coherent superposition in multi-pass amplification process

Ying Zhang, Lanqin Liu, Wang Wen-Yi, Wanqing Huang, Geng Yuan-Chao, Xie Xu-Dong, Zhu Qi-Hua

Published Jan 1, 2014• 1 citation
Publisher

Abstract

Aming at the coherent superposition of laser pulse reflected from the cavity mirror in multi-pass amplification process, a physical model for describing the amplification of coherent superstition of the rising part and the falling part of the pulse in a gain medium is established. According to theoretical analysis, standing wave is formed by the coherent superposition of the rising part and falling part of the pulse. The inversion population density shows up the effect of hole-burning by the standing wave, and the gain and pulse shape are affected. Based on this physical model, three conditions, i.e., no superposition, coherent superposition, and incoherent superposition are compared. This study will provide the instructions for high power solid laser design.

DOI
10.7498/aps.63.184205

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The multipass amplification characters of the chirped pulse in gain medium were studied with the Schrdinger equation and population equation. The inverse problem of multipass amplification of the chirped pulse was studied and simulated by means of the Split-step Fourier and iteration methods, to find the profile of the input pulse from the given output pulse and multipass amplification parameters. The results are useful for the multipass amplification and design of the pulse shaping of the chirped pulse.