SSN-2025-046-JS - Closed-Cycle Cryostat System

Colorado State University (CSU) hereby gives notice of its intent to purchase a Four9 Design Closed-Cycle Cryostat System, Item Ska-Sk300 with a full vacuum chamber and feedthrough infrastructure which will be used to create a cryogenic environment for an ion trap/optical ion clock. The CSU Department of Physics requires a complete, turnkey, high vacuum, cold environment to house these experiments. The research group is developing novel optical ion clocks, which make it possible to precisely probe Nature's fundamental symmetries. One challenge, which such clock systems have to address, are black-body-radiation-induced frequency shifts. Given that these shifts strongly scale with temperature, it is highly beneficial to probe the clock ion within a cryogenic environment and accordingly reduce the magnitude of the frequency shift. In short, the required cryo-system will host an ion trap and needs to provide adequate optical and electrical access.