Absolut System provides versatile supercritical Helium closed loops for low vibration remote cooling.

Absolut System has developed several cryocooling Helium closed loop configurations. They provide a so-called remote cooling capability by using a flexible line between a cold box, containing the cryocooler, and the application, allowing for versatile remote distributed and low vibration cooling capability. These remote supercritical Helium cooling loops are addressing, for example, the need of electro-optical characterization test benches for very large wavelength IR (VLWIR) detectors in Mercury-Cadmium-Telluride (MCT) technology in the 50-60K temperature range or MgB 2 based superconducting electro-technical equipment in the 20-30K temperature range such as motors, power cables or high field magnets.

Spatial noise characterization of IR detectors requires systematic and repetitive measurements at variable temperatures over long periods of time. In this context, Absolut System extends the temperature range of remote Helium cooling loops to address 30-200K characterization with extremely low vibration and a user-friendly press-button operation.

Remote Helium cooling loops systems have also been adapted to closed cycle cryostats with optical access. These are particularly suitable for the study of magneto-optical properties of semiconductors in the 10K region, for which extremely low vibrations are key requirements to interface with the optical table.

Thanks to this know-how developed for those realizations, Absolut System moved towards Advanced Cryogenic Equipment (ACE-CUBE), a versatile optical cryogenic platform designed for low temperature scientific instrumentation. The flexible supercritical cryogenic helium loop is a high-performance flexible line filled with pressurised Helium, minimizing the vibrations on the instrument. The key components are a cryogenic fan and a high efficiency heat exchanger, both developed and matured by Absolut System.

By mastering the components, Absolut System can provide the cryogenic solutions that meets your application specifications. This vibration-free solution can be totally customized depending on the length, power and cold temperature requirements. In order to reach temperatures lower than 4 K and keep the advantages of the flexible loop design, Absolut System is currently investigating the coupling of the two-stage pulse tube cryocooler to a Joule-Thomson cryocooler. Solutions will be proposed based on the flexible helium loop design for the range of applications between 30 K and 2 K (depending of the pressure ratio of the Joule-Thomson). Further coupling with cADR stage should allow for subK cooling.