Commentary: New developments in single photon detection in the short wavelength infrared regime

Abstract

Many new and exciting fields of scientific research rely on the efficient detection of single photons in the infrared regime. To give just two examples, quantum key distribution has the potential to offer verifiably secure methods of generating cryptographic keys and active imaging techniques permit the creation of detailed 3D models of distant objects. Currently, many of these technologies use photons in the wavelength range 400 to 1000 nm due to the ready availability of relatively efficient single photon detectors for use at these wavelengths (recent surveys may be found in Refs. [1] and [2]). However, extending the wavelength range to 1.3 µm and 1.55 µm would result in many benefits, for example compatibility with low- loss optical fiber spectral regions and atmospheric transmission windows, as well as infrared gas absorption features, notably those of greenhouse gases. Let us briefly consider the current status of the potential single photon detection technologies available for this spectral region.