Progress towards small-waist cavity arrays of Ytterbium

Atom arrays have emerged as a powerful tool for many quantum information tasks, but fast, targeted mid-circuit read-out remains a bottleneck for scalable quantum error-correction. On the other hand, cavity quantum electrodynamics (CQED) provides a powerful set of tools to study, manipulate and use light-matter interactions for quantum devices – particularly, increasing the fidelity and the speed of atom-light coupling. However, high cooperativity coupling of atom arrays to optical cavities remains an outstanding challenge. Here we present progress towards an experimental apparatus that could combine an array of Ytterbium atoms with an array of wavelength-scale waist [1] optical cavities in the strong-coupling regime. At the heart of our apparatus is an optical cavity with in-vacuum intracavity aspheres. The small waist of the cavity enables strong coupling even in the low finesse (<50) limit and allows for a variety of intra-cavity optics. An intracavity microlens array with a telescope breaks the degeneracy and creates a micron-level spaced array of cavity modes, which can then be overlapped with the atom array.

[1] https://arxiv.org/html/2407.04784v1