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arXiv · 1208.1656

An ultra-fast superconducting Nb nanowire single-photon detector for soft X-rays

Abstract

Although superconducting nanowire single-photon detectors (SNSPDs) are well studied regarding the detection of infrared/optical photons and keV-molecules, no studies on continuous X-ray photon counting by thick-film detectors have been reported so far. We fabricated a 100 nm thick niobium X-ray SNSPD (an X-SNSPD), and studied its detection capability of photons with keV-energies in continuous mode. The detector is capable to detect photons even at reduced bias currents of 0.4%, which is in sharp contrast to optical thin-film SNSPDs. No dark counts were recorded in extended measurement periods. Strikingly, the signal amplitude distribution depends significantly on the photon energy spectrum.

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Kevin Inderbitzin, Andreas Engel, Andreas Schilling, Konstantin Il'in, Michael Siegel. 2012-09-12. An ultra-fast superconducting Nb nanowire single-photon detector for soft X-rays. https://doi.org/10.1063/1.4759046

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