Speaker
Description
Superconducting nanowire single-photon detectors (SNSPDs) are a leading technology for single-photon detection in quantum science and its applications, thanks to their high detection efficiency, low noise, and unmatched timing resolution. These properties make SNSPDs attractive candidates for novel rare-event searches, such as those for axions and axion-like particles. However, the presence of strong magnetic fields generally hinders the direct, low-loss implementation of superconducting single-photon detectors within such experiments. We present our investigations of the performance and limitations of a NbTiN-based SNSPD for detecting 1064 nm photons under parallel magnetic fields of up to 6 T, while also providing insights into the underlying physics governing the nanowire’s photon response. In particular, the effect of parallel-field-induced Pauli (paramagnetic) pair breaking of spin-singlet superconductivity is discussed together with existing photon response models in the literature. Our results show that quasiparticle diffusion and multiplication play an important role in the physical processes resulting in voltage pulse after photon absorption.