Scalable ion–photon quantum interface based on integrated diffractive mirrors

Abstract

Quantum computing: high-resolution optics built directly into a micro-fabricated ion trap Building large-scale quantum computers or distributed networks of quantum computers requires small-scale nodes to be readily replicated and effectively connected. Atomic ions trapped above the surface of micro-fabricated chips are a leading method for implementing small, scalable, stationary quantum processing nodes. External communication between trapped ions has previously required bulky multi-element optics to create efficient photonic interconnections through single-mode optical fibers. Moji Ghadimi, with colleagues at Griffith University (Australia) and GeorgiaTech Research Institute, have overcome this hurdle with a demonstration of a chip trap with the primary optic integrated directly onto its surface. By patterning the flat reflective surface of the chip trap with a computer-generated hologram of a perfect focusing mirror they were able to image the ion’s fluorescence with nearly no distortions and couple that light efficiently into a single-mode fiber. This approach transfers optical complexity into the chip trap fabrication, where it can be more easily mass-produced.