Probing Terrestrial Relic Neutrino Charge with Mach-Zehnder Interferometer

We propose a novel method to probe the cosmic neutrino background (CNB) which has been shown to be accumulated on the surface of the earth. If such relic neutrino carries non-zero electric charge, Mach-Zehnder interferometer offers a suitable venue to unveil its interaction with photons. For neutrino mass equals to 0.05 eV, the sensitivity reach of our proposal could probe the fractional electric charge of the neutrino $\epsilon_{\nu}$ as low as $9.3 \times 10^{-11},\, 1.6 \times 10^{-16}$, and $2.9 \times 10^{-22}$ provided that the interferometer operates at standard quantum limit (SQL), the Heisenberg limit as well as super-Heisenberg limit, respectively.