Generation and detection of NOON states in superconducting circuits

TL;DR

This paper presents a method to generate and verify NOON states in superconducting circuits, enabling super-resolution interferometry with efficient entanglement and measurement protocols.

Contribution

It introduces a novel protocol for creating NOON states using superconducting qubits with minimal interactions and proposes an efficient verification method for large states.

Findings

Successful protocol for NOON state generation in superconducting circuits

Efficient verification method using semidefinite programming

Applicable to large NOON states with high fidelity

Abstract

NOON states, states between two modes of light of the form $|N,0\rangle+e^{i\phi}|0,N\rangle$ allow for super-resolution interformetry. We show how NOON states can be efficiently produced in circuit quntum electrodynamics using superconducting phase qubits and resonators. We propose a protocol where only one interaction between the two modes is required, creating all the necessary entanglement at the start of the procedure. This protocol makes active use of the first three states of the phase qubits. Additionally, we show how to efficiently verify the success of such an experiment, even for large NOON states, using randomly sampled measurements and semidefinite programming techniques.