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arXiv · 2204.13095

Requirements on Quantum Superpositions of Macro-Objects for Sensing Neutrinos

Eva Kilian·Marko Toroš·Frank F. Deppisch·Ruben Saakyan·Sougato Bose
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Abstract

We examine a macroscopic system in a quantum superposition of two spatially separated localized states as a detector for a stream of weakly interacting relativistic particles. We do this using the explicit example of neutrinos with MeV-scale energy scattering from a solid object via neutral-current neutrino-nucleus scattering. Presuming the (anti-)neutrino source to be a nuclear fission reactor, we utilize the estimated flux and coherent elastic neutrino-nucleus cross section to constrain the spatial separation ${\Delta}$x and describe the temporal evolution of the sensing system. Particularly, we find that a potentially measurable relative phase between quantum superposed components is obtained for a single gram scale mass placed in a superposition of spatial components separated by $10^{-14}$m under sufficient cooling and background suppression.

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Eva Kilian, Marko Toroš, Frank F. Deppisch, Ruben Saakyan, Sougato Bose. 2022-04-27. Requirements on Quantum Superpositions of Macro-Objects for Sensing Neutrinos. https://doi.org/10.1103/physrevresearch.5.023012

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