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arXiv:2401.05186

Non-inertial motion dependent entangled Bell-state

Julius Bittermann, Matthias Fink, Marcus Huber, Rupert Ursin

Published Jan 10, 2024• 0 citations
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Abstract

We show the targeted phase-manipulation of an entangled photonic Bell state via non-inertial motion. To this end, we place a very compact laboratory, consisting of a SPDC source and a Sagnac interferometer, on a rotating platform (non-inertial reference frame). The photon pairs of a $\ketϕ$-state are in a superposition of co- and counter-rotation. The phase of the $\ketϕ$-state is linearly dependent on the angular velocity of the rotating platform due to the Sagnac effect. We measure the visibility and certify entanglement with the Bell-CHSH parameter $S$. Additionally, we conduct a partial quantum state tomography on the Bell states in a non-inertial environment. Our experiment showcases the unitary transformation of an entangled state via non-inertial motion and constitutes not only a switch between a $\ket{ϕ^{-}}$-state and a $\ket{ϕ^{+}}$-state but also a further experiment at the interplay of non-inertial motion and quantum physics.

DOI
10.48550/arxiv.2401.05186

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The unification of the theory of relativity and quantum mechanics is a long-standing challenge in contemporary physics. Experimental techniques in quantum optics have only recently reached the maturity required for the investigation of quantum systems under the influence of non-inertial motion, such as being held at rest in gravitational fields, or subjected to uniform accelerations. Here, we report on experiments in which a genuine quantum state of an entangled photon pair is exposed to a series of different accelerations. We measure an entanglement witness for g-values ranging from 30 mg to up to 30 g-under free-fall as well on a spinning centrifuge-and have thus derived an upper bound on the effects of uniform acceleration on photonic entanglement.
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