Non-Perturbative Entangling Gates between Distant Qubits using Uniform Cold Atom Chains

TL;DR

This paper introduces a scalable, fast method for entangling distant qubits via uniform cold atom chains, leveraging dispersionless propagation and dynamic coupling, with potential experimental realization in optical lattices.

Contribution

It presents a novel entangling gate mechanism that does not require precise switching, is scalable with distance, and is feasible with current cold atom technologies.

Findings

Gate quality scales efficiently with qubit separation.

Gradual switching does not affect the gate mechanism.

The bus resets naturally, simplifying operation.

Abstract

We propose a new fast scalable method for achieving a two-qubit entangling gate between arbitrary distant qubits in a network by exploiting dispersionless propagation in uniform chains. This is achieved dynamically by switching on a strong interaction between the qubits and a bus formed by a non-engineered chain of interacting qubits. The quality of the gate scales very efficiently with qubit separations. Surprisingly, a sudden switching of the coupling is not necessary and our gate mechanism is not altered by a possibly gradual switching. The bus is also naturally reset to its initial state making the complex resetting procedure unnecessary after each application of the gate. Moreover, we propose a possible experimental realization in cold atoms trapped in optical lattices and near field Fresnel trapping potentials, which are both accessible to current technology.