Coherently manipulating cold ions in separated traps by their vibrational couplings

TL;DR

This paper proposes a method for coherent quantum operations between separated trapped ions using vibrational couplings, enabling scalable quantum computing beyond traditional limits.

Contribution

It introduces a new approach to perform universal quantum gates between separated ion-trap qubits via vibrational interactions, surpassing Lamb-Dicke constraints.

Findings

Demonstrates feasibility of coherent manipulations in separated ion traps

Proposes a scalable method for quantum gates using vibrational couplings

Operates beyond the Lamb-Dicke limit

Abstract

Recent experiments [K. R. Brown, et al., Nature 471, 196 (2011); and M. Harlander, et al., Nature 471, 200 (2011)] have demonstrated the coherent manipulations on the external vibrations of two ions, confined individually in the separated ion traps. Using these recently developed techniques, we propose here an approach to realize the coherent operations, e.g., the universal quantum gates, between the separated ion-trap qubits encoded by two internal atomic states of the trapped ions. Our proposal operates beyond the usual Lamb-Dicke limits, and could be applied to the scalable ion traps coupled by their vibrations.