Skip to Main content Skip to Navigation
Journal articles

Characterizing entanglement of an artificial atom and a cavity cat state with Bell’s inequality

Brian Vlastakis 1 Andrei Petrenko 1 Nissim Ofek 1 Luyan Sun 1 Zaki Leghtas 1 Katrina Sliwa 1 Yehan Liu 1 Michael Hatridge 1 Jacob Blumoff 1 Luigi Frunzio 1 Mazyar Mirrahimi 2 Liang Jiang 1 Michel H. Devoret 1 Robert Schoelkopf 1
2 QUANTIC - QUANTum Information Circuits
ENS Paris - École normale supérieure - Paris, Inria Paris-Rocquencourt, UPMC - Université Pierre et Marie Curie - Paris 6, MINES ParisTech - École nationale supérieure des mines de Paris, CNRS - Centre National de la Recherche Scientifique : UMR8551
Abstract : The Schrodinger’s cat thought experiment highlights the counterintuitive concept of entanglement in macroscopically distinguishable systems. The hallmark of entanglement is the detection of strong correlations between systems, most starkly demonstrated by the violation of a Bell inequality. No violation of a Bell inequality has been observed for a system entangled with a superposition of coherent states, known as a cat state. Here we use the Clauser–Horne–Shimony–Holt formulation of a Bell test to characterize entanglement between an artificial atom and a cat state, or a Bell-cat. Using superconducting circuits with high-fidelity measurements and real-time feedback, we detect correlations that surpass the classical maximum of the Bell inequality. We investigate the influence of decoherence with states up to 16 photons in size and characterize the system by introducing joint Wigner tomography. Such techniques demonstrate that information stored in superpositions of coherent states can be extracted efficiently, a crucial requirement for quantum computing with resonators.
Complete list of metadatas
Contributor : Mazyar Mirrahimi <>
Submitted on : Tuesday, December 8, 2015 - 6:04:21 PM
Last modification on : Wednesday, October 14, 2020 - 3:40:08 AM

Links full text



Brian Vlastakis, Andrei Petrenko, Nissim Ofek, Luyan Sun, Zaki Leghtas, et al.. Characterizing entanglement of an artificial atom and a cavity cat state with Bell’s inequality. Nature Communications, Nature Publishing Group, 2015, 6, pp.8970 ⟨10.1038/ncomms9970⟩. ⟨hal-01266469v2⟩



Record views