Rydberg Entangling Gates in Silicon

TL;DR

This paper introduces a novel Rydberg entangling gate scheme for silicon donors, achieving higher fidelity and speed, potentially overcoming key scalability challenges in quantum computing.

Contribution

The paper presents a new Rydberg gate protocol with improved fidelity and speed, including first-time calculations of electric dipole and Van der Waals interactions for donor states in silicon.

Findings

Achieves 99.9% fidelity for Bell state creation within donor excited state lifetime.

Demonstrates that Rydberg interactions are significant even for low-lying excited states.

Proposes a scalable approach to silicon-based quantum information processing.

Abstract

In this paper, we propose a new Rydberg entangling gate scheme which we demonstrate theoretically to have an order of magnitude improvement in fidelities and speed over existing protocols. We find that applying this gate to donors in silicon would help overcome the strenuous requirements on atomic precision donor placement and substantial gate tuning, which so far has hampered scaling. We calculate multivalley Rydberg interactions for several donor species using the Finite Element Method, and show that induced electric dipole and Van der Waals interactions, calculated here for the first time, are important even for low-lying excited states. We show that Rydberg gate operation is possible within the lifetime of donor excited states with 99.9% fidelity for the creation of a Bell state in the presence of decoherence.