Enhancing quantum platforms with efficient and fast photon-number-resolving superconducting nanowire single-photon detectors

Photonic platforms have led to remarkable developments in the field of quantum technologies, namely for quantum cryptography and linear-optical quantum computing. Here we report the development of high-efficiency (>90%) PNR detectors based on 1) a parallel architecture that is free of crosstalk and latching with up to 8 pixels or 2) a multi-pixel architecture with up to 14 pixels. We will discuss the different architectures with a focus on their relative advantages in terms of resolving photon numbers and in detecting at vastly increased detection rates. We will then show how they have been used in challenging experiments with a significant enhancement of the performance. First, we will report on how these detectors allowed reaching > 60 Mbps of secure key rate in a QKD experiment. Then we will show how they can be used to properly reconstruct the light statistics of coherent and thermal states, and how they allowed at 30% enhancement of the non-classicality of a heralded single-photon source. These detectors have the potential of creating close-to-perfect PNR detectors along with very short time jitters (of a few tens of picoseconds) and very short recovery time (of a few nanoseconds), which could in effect enable further photonic platforms.