High-fidelity and long-distance entangled-state transfer with Floquet topological edge modes

TL;DR

This paper introduces a robust method for generating and transferring entangled qubits over long distances using Floquet topological edge states in superconducting qubit chains, promising high fidelity and scalability.

Contribution

It presents a novel protocol leveraging Floquet topological edge modes for high-fidelity, long-distance entangled state transfer in superconducting qubit chains.

Findings

Protocol is robust against disorder and imperfections.

Effective for large system sizes due to nonvanishing energy gaps.

Enables long-distance entangled state transfer with high fidelity.

Abstract

We propose the generation of entangled qubits by utilizing the properties of edge states appearing at one end of a periodically driven (Floquet) superconducting qubit chain. Such qubits are naturally protected by the system's topology and their manipulation is possible through adiabatic control of the system parameters. By utilizing a Y-junction geometry, we then develop a protocol to perform high-fidelity transfer of entangled qubits from one end to another end of a qubit chain. Our quantum state transfer protocol is found to be robust against disorder and imperfection in the system parameters. More importantly, our proposed protocol also performs remarkably well at larger system sizes due to nonvanishing gaps between the involved edge states and the bulk states, thus allowing us in principle to transfer entangled states over an arbitrarily large distance. This work hence indicates that Floquet topological edge states are not only resourceful for implementing quantum gate operations, but also useful for high-fidelity and long-distance transfer of entangled states along solid-state qubit chains.