Temporal contrast(TC)is one of the most important parameters of an ultrahigh intense laser pulse.The third-order autocorrelator or cross correlator has been widely used in the past decades to characterize the TC of an...Temporal contrast(TC)is one of the most important parameters of an ultrahigh intense laser pulse.The third-order autocorrelator or cross correlator has been widely used in the past decades to characterize the TC of an ultraintense laser pulse.A novel and simple single-shot fourth-order autocorrelator(FOAC)to characterize the TC with higher time resolution and better pulse contrast fidelity in comparison to third-order correlators is proposed.The single-shot fourth-order autocorrelation consists of a frequency-degenerate four-wave mixing process and a sum-frequency mixing process.The proof-of-principle experiments show that a dynamic range of∼10^11 compared with the noise level,a time resolution of∼160 fs,and a time window of 65 ps can successfully be obtained using the single-shot FOAC,which is to-date the highest dynamic range with simultaneously high time resolution for single-shot TC measurement.Furthermore,the TC of a laser pulse from a petawatt laser system is successfully measured in single shot with a dynamic range of about 2×10^10 and simultaneously a time resolution of 160 fs.展开更多
基金the National Natural Science Foundation of China(NSFC)(Nos.61527821 and 61521093)the Instrument Developing Project(No.YZ201538)+1 种基金the Strategic Priority Research Program(No.XDB160106)the Chinese Academy of Sciences(CAS),and Shanghai Municipal Science and Technology Major Project(No.2017SHZDZX02)。
文摘Temporal contrast(TC)is one of the most important parameters of an ultrahigh intense laser pulse.The third-order autocorrelator or cross correlator has been widely used in the past decades to characterize the TC of an ultraintense laser pulse.A novel and simple single-shot fourth-order autocorrelator(FOAC)to characterize the TC with higher time resolution and better pulse contrast fidelity in comparison to third-order correlators is proposed.The single-shot fourth-order autocorrelation consists of a frequency-degenerate four-wave mixing process and a sum-frequency mixing process.The proof-of-principle experiments show that a dynamic range of∼10^11 compared with the noise level,a time resolution of∼160 fs,and a time window of 65 ps can successfully be obtained using the single-shot FOAC,which is to-date the highest dynamic range with simultaneously high time resolution for single-shot TC measurement.Furthermore,the TC of a laser pulse from a petawatt laser system is successfully measured in single shot with a dynamic range of about 2×10^10 and simultaneously a time resolution of 160 fs.
