Cryogenic light detectors for background suppression: The CALDER project

Next generation bolometric experiments, such as CUPID, are demanding for very competitive cryogenic light detectors. The technology for light detection must ensure an RMS noise resolution lower than 20 eV, a wide active surface (several cm ) and a high intrinsic radio-purity. Furthermore, the detectors have to be multiplexable, in order to reduce the number of electronics channels for the read-out, as well as the heat load for the cryogenic apparatus. Finally they must be characterized by a robust and reproducible behaviour, as next generation detectors will need hundreds of devices. None of the existing light detectors satisfies all these requests. In this contribution I will present the CALDER project, a recently proposed technology for light detection which aim to realize a device with all the described features.