Quantum state transfer in arrays of flux qubits

TL;DR

This paper explores the use of flux qubit arrays for quantum state transfer, analyzing fidelity and Hamiltonian properties to advance superconducting quantum communication methods.

Contribution

It proposes a realistic flux qubit chain model for high-fidelity quantum state transfer and analyzes the impact of non-conserving Hamiltonian terms.

Findings

Fidelity of state transfer calculated for flux qubit chains

Hamiltonian analysis reveals effects of non-XXZ terms

Potential for high-fidelity quantum communication in superconducting systems

Abstract

In this work, we describe a possible experimental realization of Bose's idea to use spin chains for short distance quantum communication [S. Bose, {\it Phys. Rev. Lett.} {\bf 91} 207901]. Josephson arrays have been proposed and analyzed as transmission channels for systems of superconducting charge qubits. Here, we consider a chain of persistent current qubits, that is appropriate for state transfer with high fidelity in systems containing flux qubits. We calculate the fidelity of state transfer for this system. In general, the Hamiltonian of this system is not of XXZ-type, and we analyze the magnitude and the effect of the terms that don't conserve the z-component of the total spin.