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تسجيل مستخدم جديدTable-top interferometry on extreme time and wavelength scales
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تأليف
S. Skruszewicz
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High-resolution Fourier-transform spectroscopy using table-top sources in the extreme ultraviolet (XUV) spectral range is still in its infancy. In this contribution a significant advance is presented based on a Michelson-type all-reflective split-and-delay autocorrelator operating in a quasi amplitude splitting mode. The autocorrelator works under a grazing incidence angle in a broad spectral range $mathrm{(10,nm - 1,mu m)}$ providing collinear propagation of both pulse replicas and thus a constant phase difference across the beam profile. The compact instrument allows for XUV pulse autocorrelation measurements in the time domain with a single-digit attosecond precision resulting in a resolution of $mathrm{E/Delta E=2000}$. Its performance for spectroscopic applications is demonstrated by characterizing a very sharp electronic transition at $mathrm{26.6,eV}$ in Ar gas induced by the $mathrm{11^{th}}$ harmonic of a frequency-doubled Yb-fiber laser leading to the characteristic $mathrm{3s3p^{6}4p^{1}P^{1}}$ Fano-resonance of Ar atoms. We benchmark our time-domain interferometry results with a high-resolution XUV grating spectrometer and find an excellent agreement. The common-path interferometer opens up new opportunities for short-wavelength femtosecond and attosecond pulse metrology and dynamic studies on extreme time scales in various research fields.
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