singlephotondeteksjon

Single-photon detection, known in Norwegian as "singlephotondeteksjon," refers to the technology and methods used to detect individual photons of light. This field plays a critical role in various scientific and technological applications, including quantum optics, quantum information processing, optical communication, and astrophysics. The fundamental challenge in single-photon detection is to reliably identify the arrival of a single photon amidst environmental noise and detector imperfections.

Single-photon detectors (SPDs) are designed to generate a measurable electrical signal in response to the absorption of a single photon. Several types of SPDs exist, including avalanche photodiodes (APDs), especially in Geiger mode, superconducting nanowire single-photon detectors (SNSPDs), photomultiplier tubes (PMTs), and transition-edge sensors (TES). Each type offers different advantages in terms of timing resolution, quantum efficiency, dark count rates, and operating conditions.

Avalanche photodiodes operating in Geiger mode are widely used due to their high sensitivity and relatively compact size. Superconducting nanowire detectors offer exceptional performance with high detection efficiency and low dark counts, but require cryogenic cooling. Photomultiplier tubes, an older technology, are still utilized for their large detection area and fast response.

Advancements in single-photon detection have significantly contributed to the development of quantum technologies, enabling experiments with quantum entanglement, quantum key distribution, and foundational tests of quantum mechanics. The continued improvement of detector sensitivity, efficiency, and temporal resolution remains a key focus for researchers aiming to expand the capabilities of single-photon technologies.