Événements
Séminaire IQ - Andreas Wallraff
Date : 10 mai 2024 11:00
Type : Institut Quantique
Lieu :
Lieu/Location : Auditorium de l'IQ
Language : English
Andreas Wallraff
ETH Zurich
www.qudev.ethz.ch
Titre/Title
Loophole-free Bell Inequality Violation with Superconducting Circuits
Résumé/Abstract
Superposition, entanglement, and non-locality constitute fundamental features of quantum
physics. Remarkably, the fact that quantum physics does not follow the principle of locality can be
experimentally demonstrated in Bell tests performed on pairs of spatially separated, entangled
quantum systems. While Bell tests were explored over the past 50 years, only relatively recently
experiments free of so-called loopholes succeeded. Here, we demonstrate a loophole-free
violation of Bell’s inequality with superconducting circuits [1]. To evaluate a CHSH-type Bell
inequality, we deterministically entangle a pair of qubits and perform fast, and high-fidelity
measurements along randomly chosen bases on the qubits connected through a cryogenic link
spanning 30 meters. Evaluating more than one million experimental trials, we find an average S-
value of 2.0747 ± 0.0033, violating Bell’s inequality by more than 22 standard deviations. Our work
demonstrates that non-locality is a viable new resource in quantum information technology
realized with superconducting circuits with applications in quantum communication, quantum
computing and fundamental physics.
[1] S. Storz, J. Schär, A. Kulikov, P. Magnard, P. Kurpiers, J. Lütolf, T. Walter, A. Copetudo, K.
Reuer, A. Akin, J-C. Besse, M. Gabureac, G. J. Norris, A. Rosario, F. Martin, J. Martinez, W.
Amaya, M. W. Mitchell, C. Abellán, J-D. Bancal, N. Sangouard, B. Royer, A. Blais, and A. Wallraff,
Nature 617, 265-270 (2023)
* Work done in collaboration with Simon Storz, Josua Schaer, Anatoly Kulikov, Paul Magnard,
Philipp Kurpiers, Janis Luetolf, Theo Walter, Adrian Copetudo, Kevin Reuer, Abdulkadir Akin,
Jean-Claude Besse, Mihai Gabureac, Graham J. Norris, Andres Rosario, Ferran Martin, Jose
Martinez, Waldimar Amaya, Morgan W. Mitchell, Carlos Abellan, Jean-Daniel Bancal, Nicolas
Sangouard, Baptiste Royer, Alexandre Blais, and Andreas Wallraff
Language : English
Andreas Wallraff
ETH Zurich
www.qudev.ethz.ch
Titre/Title
Loophole-free Bell Inequality Violation with Superconducting Circuits
Résumé/Abstract
Superposition, entanglement, and non-locality constitute fundamental features of quantum
physics. Remarkably, the fact that quantum physics does not follow the principle of locality can be
experimentally demonstrated in Bell tests performed on pairs of spatially separated, entangled
quantum systems. While Bell tests were explored over the past 50 years, only relatively recently
experiments free of so-called loopholes succeeded. Here, we demonstrate a loophole-free
violation of Bell’s inequality with superconducting circuits [1]. To evaluate a CHSH-type Bell
inequality, we deterministically entangle a pair of qubits and perform fast, and high-fidelity
measurements along randomly chosen bases on the qubits connected through a cryogenic link
spanning 30 meters. Evaluating more than one million experimental trials, we find an average S-
value of 2.0747 ± 0.0033, violating Bell’s inequality by more than 22 standard deviations. Our work
demonstrates that non-locality is a viable new resource in quantum information technology
realized with superconducting circuits with applications in quantum communication, quantum
computing and fundamental physics.
[1] S. Storz, J. Schär, A. Kulikov, P. Magnard, P. Kurpiers, J. Lütolf, T. Walter, A. Copetudo, K.
Reuer, A. Akin, J-C. Besse, M. Gabureac, G. J. Norris, A. Rosario, F. Martin, J. Martinez, W.
Amaya, M. W. Mitchell, C. Abellán, J-D. Bancal, N. Sangouard, B. Royer, A. Blais, and A. Wallraff,
Nature 617, 265-270 (2023)
* Work done in collaboration with Simon Storz, Josua Schaer, Anatoly Kulikov, Paul Magnard,
Philipp Kurpiers, Janis Luetolf, Theo Walter, Adrian Copetudo, Kevin Reuer, Abdulkadir Akin,
Jean-Claude Besse, Mihai Gabureac, Graham J. Norris, Andres Rosario, Ferran Martin, Jose
Martinez, Waldimar Amaya, Morgan W. Mitchell, Carlos Abellan, Jean-Daniel Bancal, Nicolas
Sangouard, Baptiste Royer, Alexandre Blais, and Andreas Wallraff