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

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.

Ultraviolet thermoelectric single photon detector with high signal-to-noise ratio

“…In addition to their advantages in classical imaging applications with laser-driven UV sources, the ability to count single photons opens up promising prospects for applications in quantum optics and quantum imaging involving high-energy radiation, such as quantum ghost imaging with nanoscale resolution. 14 Along with the accomplishments attained, the progress in science and technology necessitates the creation of faster detectors with higher detection efficiency and improved energy resolution. The possibilities for technological advancements that are required to elevate SNSPDs to the next level, encompassing photon-counting, fast time-tagging imaging, and multi-pixel technology compatible with quantum photonic integrated circuits, are presented in Ref.…”

“… – 11 However, superconducting nanowire single-photon detectors (SNSPDs) exhibit superior characteristics 12 – 14 The design, fabrication, and characterization of SNSPDs operating at wavelengths ranging from 250 to 370 nm were studied 12 . These detectors feature active areas up to 56 μm in diameter, exhibit 70% to 80% efficiency at temperatures up to 4.2 K, offer timing resolution down to 60 ps [full width at half maximum (FWHM)], are insensitive to visible and infrared photons, and demonstrate dark count rates of ∼0.25 cph.…”

“…These detectors are free from dark counts and can operate at high count rates. In addition to their advantages in classical imaging applications with laser-driven UV sources, the ability to count single photons opens up promising prospects for applications in quantum optics and quantum imaging involving high-energy radiation, such as quantum ghost imaging with nanoscale resolution 14 …”