Single-shot cross-correlator using a long-wavelength sampling pulse

We present a single-shot cross-correlating scheme capable of high dynamic range and large temporal window for pulse contrast characterization. By adopting a long-wavelength sampling pulse parametrically converted from the pulse under test, wavelength combination in the correlating process allows the use of a large noncollinear phase-matching angle in periodically poled lithium niobate crystal, matches the high-sensitivity detection system consisting of a fiber array and a photomultiplier tube, and favors the elimination of optical scattering noise. The prototype experiments demonstrate a detectable contrast maximum up to ～10(9), temporal window of ～50?ps, and resolution of ～1?ps, using <0.5?mJ input energy.