Using macroscopic entanglement to close the detection loophole in Bell-inequality tests

2011/12/31 by Youngrong Lim, Mauro Paternostro, Jinhyoung Lee +2
Computer Science · Physics and Astronomy · #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum Mechanics and Applications #quant-ph

paper · pdf · doi:10.1103/physreva.85.062112

published as Phys. Rev. A 85, 062112 (2012) · 5 pages, 5 figures, to be published in Phys. Rev. A

arxiv created 2012/06/01 · openalex publication_date 2012/06/19 · arxiv updated 2012/06/22 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/01

Abstract

We consider a Bell-like inequality performed using various instances of multiphoton entangled states to demonstrate that losses occurring after the unitary transformations used in the nonlocality test can be counteracted by enhancing the size of such entangled states. In turn, this feature can be used to overcome detection inefficiencies affecting the test itself: a slight increase in the size of such states, pushing them towards a more macroscopic form of entanglement, significantly improves the state robustness against detection inefficiency, thus easing the closing of the detection loophole. Differently, losses before the unitary transformations cause decoherence effects that cannot be compensated using macroscopic entanglement.

Citations

• Violation of Bell's inequality under strict Einstein locality conditions
• Bell Inequality Violation with Two Remote Atomic Qubits
• Transfer of Nonclassical Properties from A Microscopic Superposition to Macroscopic Thermal States in The High Temperature Limit
• Hybrid methods for witnessing entanglement in a microscopic-macroscopic system
• Violation of Bell’s inequality using classical measurements and nonlinear local operations
• On the Einstein Podolsky Rosen paradox