Doubling the Operating Temperature of High Efficiency UV Superconducting Nanowire Detectors

Future high-precision UV astronomy and astrophysics observations require detectors which have high detection efficiencies, are solar-blind, and ideally are single-photon sensitive. Presently, there are only a few detector types available for missions in the wavelength range of 90-400 nm. Notably missing are superconducting nanowire single-photon detectors (SNSPD), which have been demonstrated to have very high detection efficiencies (> 90% in the infrared at 1550 nm,~ 80% in the UV at 370 nm), insensitivity to low-energy photons (excellent solar blindness), and high dynamic range (>9 orders of magnitude). The performance of an SNSPD-based imager would be a valuable addition to the UV detection toolkit available for future space telescopes such as LUVOIR.

However, these detectors currently operate at or below liquid helium (4K) temperatures. This requirement presents a significant challenge to implementation – the closer to absolute zero, the more cryogenic infrastructure is required. In order to bring a valuable UV detector technology closer to implementation in future missions, we propose to develop a high-efficiency UV SNSPD with an operating temperature of 8K, twice that of previous work. Bringing the operating temperature up to 8K would significantly reduce the cryogenic infrastructure needed for potential future missions, and such a detector based on superconducting nanowires would meet and exceed the requirements for future space telescopes such as LUVOIR.

The principal objective of the proposed work is to develop and demonstrate SNSPDs with an operation temperature twice as high as previously demonstrated—bringing them to an operating temperature of 8K from the current state-of-the-art temperature of 4K. To demonstrate this capability, we propose a small two-year program to take these higher-temperature detectors from TRL 2 to TRL 3. In this program, we will perform over 12 complete fabrication-to-experimental cycles, including material deposition, material characterization, lithography and etch characterization, and measurements of the fabricated detectors. In this process, we will also be characterizing the detectors and their thin films from 120nm to 400nm to validate their relevance to the needs of future missions.

Ultimately, this work will position these detectors well for future implementation in imaging arrays and ultimately, a mission in the 2030s. My goal is to continue to demonstrate (and improve) the utility of these detectors for the next two decades, with the goal of making them an attractive UV detector candidate for future space telescopes such as LUVOIR. To that end, this work will mesh well with the currently-funded APRA we are working on to integrate these single-pixel detectors into a large imaging array. After that point, the next target of research for these detectors will be building a proof-of-principle UV spectral imaging experiment that can highlight the extremely good efficiency, low background, and solar blindness of these detectors.

The goals of the Nancy Grace Roman Technology Fellowship (RTF) program in astrophysics are to provide early-career researchers the opportunity to develop the skills necessary to lead astrophysics flight instrument development projects, including suborbital investigations, in preparation to become Principal Investigators (PIs) of future NASA astrophysics missions; to develop innovative technologies for space astrophysics that have the potential to enable major scientific breakthroughs; and to foster new talents by putting early career instrument builders on a trajectory towards long-term positions.

This is a mature technology (TRL 7+) — the realistic path in is usually NASA's Technology Transfer Program: licensing an existing NASA patent, or a Space Act Agreement to use NASA facilities/expertise directly. NASA also runs a startup licensing program with no upfront fee for companies formed to commercialize a specific NASA technology.

None of these are guaranteed paths for this specific project — TechPort itself doesn't have an "apply" button. Reaching out to the contact(s) above with a specific question is usually the fastest way to find out what's actually open.