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Quantum steering with rotation-invariant twisted photons with the detection loophole closed

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 نشر من قبل Sergei Slussarenko
 تاريخ النشر 2020
  مجال البحث فيزياء
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Violating a nonlocality inequality enables the most powerful remote quantum information tasks and fundamental tests of physics. Loophole-free photonic verification of nonlocality has been achieved with polarization-entangled photon pairs, but not with states entangled in other degrees of freedom. Here we demonstrate completion of the quantum steering nonlocality task, with the detection loophole closed, when entanglement is distributed by transmitting a photon in an optical vector vortex state, formed by optical orbital angular momentum (OAM) and polarization. The demonstration of vector vortex steering opens the door to new free-space and satellite-based secure quantum communication devices and device-independent protocols.



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