Searches for massive neutrinos with mechanical quantum sensors

TL;DR

This paper proposes using quantum optomechanical sensors to detect heavy sterile neutrinos and measure neutrino masses by observing recoil from nuclear decays, leveraging quantum control of mechanical sensors.

Contribution

It introduces a novel method employing nanomechanical sensors to search for sterile neutrinos and measure neutrino masses with unprecedented sensitivity.

Findings

Potential to detect heavy sterile neutrinos in the keV-MeV range

Sensor sensitivity surpasses existing experimental constraints

Possibility of measuring absolute neutrino mass with quantum sensors

Abstract

The development of quantum optomechanics now allows mechanical sensors with femtogram masses to be controlled and measured in the quantum regime. If the mechanical element contains isotopes that undergo nuclear decay, measuring the recoil of the sensor following the decay allows reconstruction of the total momentum of all emitted particles, including any neutral particles that may escape detection in traditional detectors. As an example, for weak nuclear decays the momentum of the emitted neutrino can be reconstructed on an event-by-event basis. We present the concept that a single nanometer-scale, optically levitated sensor operated with sensitivity near the standard quantum limit can search for heavy sterile neutrinos in the keV-MeV mass range with sensitivity significantly beyond existing constraints. We also comment on the possibility that mechanical sensors operated well into the quantum regime might ultimately reach the sensitivities required to provide an absolute measurement of the mass of the light neutrino states.