Imaging of Trapped Ions with a Microfabricated Optic for Quantum Information Processing

Trapped ions are a leading system for realizing quantum information processing (QIP). Most of the technologies required for implementing large-scale trapped-ion QIP have been demonstrated, with one key exception: a massively parallel ion-photon interconnect. Arrays of microfabricated phase Fresnel lenses (PFL) are a promising interconnect solution that is readily integrated with ion trap arrays for large-scale QIP. Here we show the first imaging of trapped ions with a microfabricated in-vacuum PFL, demonstrating performance suitable for scalable QIP. A single ion fluorescence collection efficiency of 4.2 +/- 1.5% was observed. The depth of focus for the imaging system was 19.4 +/- 2.4 mu m and the field of view was 140 +/- 20 mu m. Our approach also provides an integrated solution for high-efficiency optical coupling in neutral atom and solid-state QIP architectures.