Toolbox of resonant quantum gates in Circuit QED

TL;DR

This paper introduces fast resonant quantum gates in circuit QED using three-level superconducting qubits, enabling efficient two-qubit operations and cluster state generation with improved speed and fidelity.

Contribution

It presents a novel method for implementing rapid resonant gates in circuit QED, enhancing quantum information processing capabilities.

Findings

Resonant gates outperform dispersive techniques in speed.

Cluster state generation time scales linearly with qubit number.

Achieved over 60% fidelity for a 3x3 cluster state considering decoherence.

Abstract

We propose the implementation of fast resonant gates in circuit quantum electrodynamics for quantum information processing. We show how a suitable utilization of three-level superconducting qubits inside a resonator constitutes a key tool to perform diverse two-qubit resonant gates, improving the operation speed when compared to slower dispersive techniques. To illustrate the benefit of resonant two-qubit gates in circuit QED, we consider the implementation of a two-dimensional cluster state in an array of N x N superconducting qubits by using resonant controlled-phase (CPHASE) and one-qubit gates, where the generation time grows linearly with N. For N=3, and taking into account decoherence mechanisms, a fidelity over 60% for the generation of this cluster state is obtained.