Single-Shot Temporal Contrast Enhancement Measurement of a Plasma Mirror by a Chirped Pulse

Dongjun Zhang,Yan Liang,Qi Gao,Haidong Zhu,Jianqiang Zhu,Jun Kang,Youjian Yi,Ailin Guo,Cheng Liu,Qingwei Yang,Meizhi Sun,Xinglong Xie,Ping Zhu,Xiao Liang,Linjun Li

doi:10.3390/app11219967

Abstract

We focused on a single-shot method for directly measuring the temporal contrast enhancement of a single plasma mirror by analyzing the spectrum of a chirped pulse spatiotemporally overlapped with the igniting laser used for generating a plasma mirror. Experimentally, temporal contrast enhancement of 102 by one plasma mirror was successfully measured in a hundred picosecond timescale and was consistent with the theory. This single-shot measurement method caused no degradation on the performance of the plasma mirror, which was proved by monitoring the efficiency and far-field pattern of the igniting laser after the plasma mirror. Combined with calorimeters and CCD cameras, this method is expected to realize the single-shot online diagnosis of plasma mirrors. This method is expected to be an efficient approach for measuring the temporal contrast enhancement of the plasma mirrors.

Highlights

In the past three decades, high-power ultrashort pulse lasers have been significantly improved with the rapid development of femtosecond technology and chirped pulse amplification (CPA) [1]
The undesired temporal noises are always in existence accompanied by the amplified spontaneous emission, parametric fluorescence, and temporal phase modulation during the process of CPA or optical parametric chirped pulse amplification (OPCPA) [9]
To suppress the temporal noises of the pulses, various of pulse-cleaning techniques have been reported, including saturable absorber (SA) [11], cross-polarized wave generation (XPW) [12], Fourier-filtering [13], picosecond optical parametric amplification [14] applied before compression, frequency doubling by second harmonic generation (SHG) [15], and plasma mirrors (PMs) [16,17,18] applied after compression

Summary

Introduction

In the past three decades, high-power ultrashort pulse lasers have been significantly improved with the rapid development of femtosecond technology and chirped pulse amplification (CPA) [1]. The undesired temporal noises are always in existence accompanied by the amplified spontaneous emission, parametric fluorescence, and temporal phase modulation during the process of CPA or optical parametric chirped pulse amplification (OPCPA) [9]. These temporal noises appear as the pulse pedestals, coherent wings, and leading edge of the main pulse [10], and even strong pre-pulses, interacting with the target prior to the main pulse and eventually resulting in unsatisfactory experimental results. To suppress the temporal noises of the pulses, various of pulse-cleaning techniques have been reported, including saturable absorber (SA) [11], cross-polarized wave generation (XPW) [12], Fourier-filtering [13], picosecond optical parametric amplification (ps-OPA) [14] applied before compression, frequency doubling by second harmonic generation (SHG) [15], and plasma mirrors (PMs) [16,17,18] applied after compression

Methods

Results

Discussion

Conclusion