Requirements on Quantum Superpositions of Macro-Objects for Sensing Neutrinos

TL;DR

This paper explores the feasibility of using macroscopic quantum superpositions as detectors for neutrinos, analyzing the conditions needed for measurable phase shifts in such systems.

Contribution

It provides explicit requirements for creating and maintaining quantum superpositions of macro-objects to detect weakly interacting neutrinos.

Findings

Measurable phase shifts possible with gram-scale superpositions.

Superpositions separated by 10^{-14} meters can detect neutrino interactions.

Cooling and background suppression are critical for detection.

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.