In situ frequency gating and beam splitting of vacuum- and extreme-ultraviolet pulses  

作　　者：Rajendran Rajeev Johannes Hellwagner Anne Schumacher Inga Jordan Martin Huppert Andres Tehlar Bhargava Ram Niraghatam Denitsa Baykusheva Nan Lin Aaron von Conta Hans Jakob Wörner 

机构地区：[1]Laboratory of Physical Chemistry,Department of Chemistry and Applied Biosciences,Vladimir-Prelog-Weg 2,ETH Zurich,Zurich 8093,Switzerland

出　　处：《Light(Science & Applications)》2016年第1期396-402,共7页光（科学与应用)（英文版）

基　　金：support from a starting grant(project No.307270-ATTOSCOPE)of the European Research Council;the Swiss National Science Foundation via the National Centre of Competence in Research Molecular Ultrafast Science and Technology.

摘　　要：Monochromatization of high-harmonic sources has opened fascinating perspectives regarding time-resolved photoemission from all phases of matter.Such studies have invariably involved the use of spectral filters or spectrally dispersive optical components that are inherently lossy and technically complex.Here we present a new technique for the spectral selection of near-threshold harmonics and their spatial separation from the driving beams without any optical elements.We discover the existence of a narrow phase-matching gate resulting from the combination of the non-collinear generation geometry in an extended medium,atomic resonances and absorption.Our technique offers a filter contrast of up to 104 for the selected harmonics against the adjacent ones and offers multiple temporally synchronized beamlets in a single unified scheme.We demonstrate the selective generation of 133,80 or 56 nm femtosecond pulses from a 400-nm driver,which is specific to the target gas.These results open new pathways towards phase-sensitive multi-pulse spectroscopy in the vacuum-and extreme-ultraviolet,and frequencyselective output coupling from enhancement cavities.

关 键 词：beam splitting below-threshold harmonics coherent extreme-ultraviolet pulses frequency gating non-collinear generation 

分 类 号：TN2[电子电信—物理电子学]