Photon counting of extreme ultraviolet high harmonics using a superconducting nanowire single-photon detector

Silvio Fuchs,Christian Rödel,Slawomir Skruszewicz,Martin Wünsche,Jan Nathanael,Julius Reinhard,Johann J Abel,Gerhard G Paulus,Heidemarie Schmidt,Detlef Born,Felix Wiesner

doi:10.1007/s00340-022-07754-6

Abstract

Laser-driven light sources in the extreme ultraviolet range (EUV) enable nanoscopic imaging with unique label-free elemental contrast. However, to fully exploit the unique properties of these new sources, novel detection schemes need to be developed. Here, we show in a proof-of-concept experiment that superconducting nanowire single-photon detectors (SNSPD) can be utilized to enable photon counting of a laser-driven EUV source based on high harmonic generation (HHG). These detectors are dark-count free and accommodate very high count rates—a perfect match for high repetition rate HHG sources. In addition to the advantages of SNSPDs for classical imaging applications with laser-driven EUV sources, the ability to count single photons paves the way for very promising applications in quantum optics and quantum imaging with high energetic radiation like, e.g., quantum ghost imaging with nanoscale resolution.

Highlights

The ability to visualize small features down to the nanoscale has ever since been an important key to scientific and technological advances
Our findings prove that a single-photon detector based on superconducting nanowires can be utilized for photon counting of extreme ultraviolet (EUV) photons in particular from a laser-driven high harmonic generation (HHG) source with very low dark count rates
Novel fiber-laser approaches for high-power laboratory-based HHG sources are realized by drastically increasing the repetition rate up to the MHz [45] regime so that the high possible count-rate of the superconducting nanowire single-photon detectors (SNSPD) can be exploited in the future

Summary

Introduction

The ability to visualize small features down to the nanoscale has ever since been an important key to scientific and technological advances. A variety of photon counting semiconducting detectors like avalanche photo diodes [22] or electron-multiplier-CCD detectors [23] are available but mostly for the infrared and optical wavelength range These devices typically exhibit no or very low detection efficiency for EUV and SXR photons and their count rates are typically much smaller than the repetition rate of high flux HHG sources. We demonstrate that superconducting nanowire single-photon detectors (SNSPDs) [26], which originally were designed for infrared radiation [27], can directly be utilized for photon counting of EUV radiation from laser-driven high harmonic sources. Depending on the photon energy the absorption in the 10 nm-thin NbN

Results

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Conclusion

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