Searches for Massive Neutrinos with Mechanical Quantum Sensors

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 laboratory 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.

Automated summary

The development of quantum optomechanics has allowed for control and measurement of mechanical sensors in the quantum regime. By measuring the recoil of sensors containing isotopes that undergo nuclear decay, it is possible to reconstruct the total momentum of all emitted particles, including neutrinos. A nanometer-scale optically levitated sensor operated near the standard quantum limit can search for heavy sterile neutrinos and potentially measure the mass of light neutrino states.