Towards the detection of ultra-low energetic neutrinos with plasma metamaterials

Abstract

Theoretical works showed the existence of neutrino flux with energy below eV, the detection of these low energetic neutrino can shed light on Dark Matter problem along with the improvement of the Standard Model; the detector used nowadays are not able to detect such energies, in this thesis we propose a technique to detect slow flux of massive neutrino by plasmon generation. Through the semiclassical approximation of the Weak Interaction, we derived the force felt by a plasma due to the neutrino distribution, and vice-versa; therefore, by the Kinetic description with linear perturbation approach, we studied the interaction of electron plasma and neutrino flux. The long lifetime of plasmon in graphene structures oriented us to study bidimensional (2D) electron systems; the Weak interaction, between neutrino and ungated electron solid-state plasma, leads to a feature alike the beam-plasma instability, raising the possibility to have a growth rate. The generated plasmon has Wavevector dependent on the neutrino velocity and spectral width function of the neutrino’s density and mass; the instability was considered in an effective tridimensional (3D) metamaterial obtained by graphene heterostructure, the resulting Signal to Noise ratio (SN) is mainly dependent on the length of the device. Larger growth rates are found for lower neutrino energy and larger density: with detector size in the order of centimeters, the detection of neutrino with energy µeV is ensured for flux above 105 cm−2 with SN about 10 dB, for meV neutrino the same SN is ensured for flux above 1012 cm−2 .