Ion-photon quantum interface : entanglement engineering.

Distributed quantum information processing requires a reliable quantum memory and a faithful carrier of quantum information. Trapped ion qubits are the leading realization for quantum information storage, and photonic qubits are the natural choice for the transport of quantum information. The capability to entangle photons with trapped ions in a highly efficient (scalable) fashion is an important achievement. Here, we leverage the active and successful development of micro-fabricated semiconductor ion traps at the Sandia National Laboratory MESA facility, and integrate micro optical components. Compared to current efforts in academic settings combining macro-sized ion traps and optics, a micro device will result in the dramatically increased speed and fidelity of ion-trap based quantum networking protocols. Integrating smaller components will directly allow for a stronger quantum coherent interface between a single trapped ion and a single photon. If successful, this technology could lead to new demonstrations of fundamental physics properties and would open new avenues for scalable quantum networking architectures.