Speaker
Description
The TESSERACT (Transition Edge Sensors with Sub-eV Resolution And Cryogenic Targets) experiment is an international collaboration between the USA, France, and Switzerland that aims to search for light dark matter over a wide range of masses (from the proton mass down to a few meV) at the Modane Underground Laboratory (LSM). To achieve this goal, it will utilize different cryogenic detector technologies made from various target materials: superfluid helium, polar crystals, and Ge or Si bolometers. For Ge and Si, two different technologies are being developed, both based on aluminum electrodes evaporated onto the surface of the crystals with a bias voltage applied to them. In one case, this bias is low (<10 V), and the detector is equipped with a phonon sensor and a charge readout. This dual-measurement approach allows for discrimination between nuclear recoil-induced events and electronic recoil events, providing a way to reject background events. In the second case, the bias voltage is high (>50 V), focusing on the detection of Neganov-Trofimov-Luke phonons using a point-contact NbSi TES, which boosts the signal to achieve single electron/hole pair sensitivity.
In this talk, I will present the most recent advancements in both of these technologies and present the prospects for their integration into the TESSERACT experiment.