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Compact 1.7 K Cryocooler for Superconducting Nanowire Single-Photon Detectors



Vincent Y. Kotsubo, Joel N. Ullom, Sae Woo Nam


State-of-the-art superconductor-based cryogenic detector systems are being installed at numerous research facilities worldwide and are achieving world-record sensitivities in a variety of applications. Implementation has been greatly facilitated by closed-cycle refrigeration. However, in many cases, cooling capacities of the refrigerators exceed requirements, at times by orders of magnitude, resulting in excessively large and cumbersome systems. The availability of more compact and lower power consumption systems should greatly facilitate further user acceptance. Toward this end, we are developing a compact 1.7 K closed-cycle pulse tube/Joule-Thomson hybrid cryocooler for superconducting nanowire single-photon detectors. A laboratory prototype consisting of the pulse tube cooler and the Joule-Thomson coldhead has demonstrated over 1.4 mW of cooling at 1.7 K. The Joule-Thomson compressor is under development and remains the single largest risk item in terms of reliability. The system, designed for low manufacturing costs, is projected to consume on the order of 250 W total power, including power for cooling fans, thermometry, and detector electronics, and to be mountable within a standard equipment rack.
Proceedings Title
Cryocoolers 20
Conference Dates
June 18-21, 2018
Conference Location
Burlington, VT
Conference Title
20th International Cryocooler Conference


cryocooler, cryogenics, pulse tube, Joule-Thomson, superconducting nanowire single photon detector, superconductivity, refrigerator, cooling fans, thermometry, detector electronics, mountable


Kotsubo, V. , Ullom, J. and Nam, S. (2020), Compact 1.7 K Cryocooler for Superconducting Nanowire Single-Photon Detectors, Cryocoolers 20, Burlington, VT, [online], (Accessed April 18, 2024)
Created June 17, 2020, Updated July 15, 2020