NPA Seminar, Wouter van de Pontseele, MIT, “Quantum technologies for neutrino measurements”

Superconducting technologies have been developed and employed with great success by the quantum information science community. More and more, these technologies show promise for fundamental physics. I want to sketch some of their possible advantages in the context of the Ricochet and Project 8 neutrino experiments.
The Ricochet experiment aims to detect coherent elastic neutrino-nucleus scattering at the nuclear research reactor in Grenoble, France. The experiment will start data-taking in 2024 with two complementary detector technologies, both employing cryogenic calorimeters. One of the two detector technologies envisaged by Ricochet has a target mass consisting of superconducting crystals.
When a neutrino interacts coherently with a nucleus in a superconducting crystal lattice, the recoil energy produces phonons and excites cooper pairs into Bogoliubov quasiparticles. The milli-electronvolt-scale bandgap of superconductors might enable a significantly lower nuclear recoil energy threshold.
To sense the energy in the phonon and quasiparticle systems, a trapping and thermalisation layer is connected with transition edge sensors for ultra-sensitive heat to current conversion. Several detectors are envisaged to be frequency multiplexed into the microwave band at cryogenic temperatures using SQUIDs and resonators.
Finally, I will touch upon the development of Travelling Wave Parametric Amplifiers (TWPA) at MIT, a class of quantum-limited amplifiers appropriate for broadband microwave amplification that could suit both Project 8 and Ricochet.