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arXiv · 1211.2557

Single-shot spectra of temporally selected micropulses from a mid-infrared free-electron laser by upconversion

Xiaolong Wang·Takashi Nakajima·Heishun Zen·Toshiteru Kii·Hideaki Ohgaki
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Abstract

We demonstrate the measurement of single-shot spectra of temporally selected micropulses from a mid-infrared (MIR) free-electron laser (FEL) by upconversion. We achieve the upconversion of FEL pulses at 11 μm using externally synchronized Nd:YAG or microchip laser pulses at 1064 nm to produce sum-frequency mixing (SFM) signals at 970 nm, which are detected by a compact CCD spectrometer without an intensifier. Our experimental system is very cost-effective, and allows us to obtain the laser spectra of selected micropulses at any temporal position within a single macropulse from an oscillator-type FEL.

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Xiaolong Wang, Takashi Nakajima, Heishun Zen, Toshiteru Kii, Hideaki Ohgaki. 2012-11-27. Single-shot spectra of temporally selected micropulses from a mid-infrared free-electron laser by upconversion. https://doi.org/10.1364/ol.37.005148

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