We are exploring the combination of atom chips with microfabricated optical cavities to enable strong atom-photon coupling in a scalable system.
We have demonstrated a scalable micro-mirror suitable for atom chip based cavity quantum electrodynamics (cQED) applications (see Figure 1). A very low surface roughness of 2.2 Angstroms rms on the silicon cavity mirrors is achieved using chemical dry etching along with plasma and oxidation smoothing.
Our Fabry-Perot cavity comprised of these mirrors currently demonstrates the highest finesse, F = 64,000, using microfabricated mirrors. We compute a single atom cooperativity for our cavities of more than 200, making them promising candidates for detecting individual atoms and for quantum information applications on a chip (see Figure 2).
The fabrication process used here is compatible with production techniques for atom chips which allow for intercavity transport and precision positioning of laser cooled neutral atoms. The combination of these technologies may enable devices delivering large arrays of atom-cavity systems for use in quantum information applications. We are currently fabricating a two-layer atom chip with integrated micro-mirrors.