Generation and detection of NOON states in superconducting circuits

Abstract

NOON states, states between two modes of light of the form |N, 0⟩+eiϕ|0,N⟩, are highly nonclassical entangled states with applications in super-resolution interferometry. We show how NOON states can be efficiently produced in circuit quantum 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.