Prospects for fast Rydberg gates on an atom chip

TL;DR

This paper explores the feasibility of implementing fast, high-fidelity Rydberg-based two-qubit gates on atom chips, addressing challenges like spontaneous emission and surface noise to advance scalable quantum computing.

Contribution

It introduces an optimal control approach to design the shortest possible Rydberg phase gate with acceptable error rates on atom chips, even outside the Rydberg blockade regime.

Findings

Optimal control yields fast gate times with manageable errors.

Surface noise impacts Rydberg state coherence.

Spontaneous emission influences gate fidelity.

Abstract

Atom chips are a promising candidate for a scalable architecture for quantum information processing provided a universal set of gates can be implemented with high fidelity. The difficult part in achieving universality is the entangling two-qubit gate. We consider a Rydberg phase gate for two atoms trapped on a chip and employ optimal control theory to find the shortest gate that still yields a reasonable gate error. Our parameters correspond to a situation where the Rydberg blockade regime is not yet reached. We discuss the role of spontaneous emission and the effect of noise from the chip surface on the atoms in the Rydberg state.