Generalized switchable coupling for superconducting qubits using double resonance

TL;DR

This paper introduces a double resonance technique for switchable coupling in superconducting qubits, enabling entangling gates with relaxed driving requirements and addressing limitations of previous methods.

Contribution

It presents a novel double resonance approach for switchable qubit coupling that reduces the need for strong driving fields and improves upon prior proposals.

Findings

Achieves switchable coupling via near-resonant oscillating fields

Allows for fully entangling two-qubit gates with relaxed driving conditions

Potentially applicable to flux and phase qubits

Abstract

We propose a method for switchable coupling between superconducting qubits using double resonance. The inter-qubit coupling is achieved by applying near-resonant oscillating fields to the two qubits. The deviation from resonance relaxes the criterion of strong driving fields while still allowing for a fully entangling two-qubit gate. This method avoids some of the shortcomings of previous proposals for switchable coupling. We discuss the possible application of our proposal to a pair of inductively coupled flux qubits, and we consider the extension to phase qubits.