Towards a cryogenic apparatus for beryllium, magnesium, calcium ion trap experiments

I will discuss the upgrade of a mixed-species experimental apparatus to a cryogenic system capable of supporting multi-zone surface-electrode traps. Cryogenic vacuum environments have the benefit of more rapidly achieving ultra-high vacuum, offer lower base pressures compared to a room-temperature apparatus, and broaden the range of materials that can be used in vacuum. Lower base pressures will allow for longer ion lifetimes than possible in the current 3D trap, despite the shallower trapping potential of surface-electrode traps. For example, ⁴⁰Ca⁺ has been shown to remain trapped in a surface electrode trap in an identical apparatus for several hours without any cooling light. Having long ion lifetimes and the ability to support large numbers of ions are key to scaling up experiments and crucial for efforts towards the realization of trapped-ion quantum processors with many qubits. Additionally, the ability to quickly reach base operating pressure permits rapid trap exchange, ultimately providing the ability to more rapidly prototype trap designs; some of the first traps to be installed will feature a novel junction design, a trap-integrated superconducting nanowire single photon detector, or other trap-integrated photonics which show promise for use within the QCCD architecture.