A world leader in the design and development of ultrafast femtosecond and picosecond infra-red lasers is helping researchers characterize single photon detectors (SPDs), essential for many applications such as quantum key distribution, LIDAR, and sensing and characterization of samples using fluorescence lifetime measurement.
Chromacity lasers helping to understand the behaviour of single photon detectors (SPDs). Image Credit: Chromacity
Researchers are pushing to develop single photon detectors to operate in the near and mid-infrared. Infrared light is less susceptible to atmospheric absorption and can be particularly advantageous for free space applications such as long-range LIDAR. New technologies such as Superconducting nanowire single-photon detectors (SNSPDs or SSPDs) have a very high photon detection efficiency and very low timing jitter, making them suitable for many of these single-photon applications.
However, testing and validating new sensor characteristics can be challenging – until now. This new generation of sensors is sensitive to a wide wavelength range, so a source capable of scanning the complete wavelength range is important to create a complete picture of performance. The time domain performance is also affected by the wavelength of the incident light, so being able to probe the sensor with a low-jitter photon pulse is essential.
Chromacity has developed a family of tuneable ultrafast infrared lasers that are ideal partners for SPD testing. The Auskerry laser is capable of continuous tuning across 1.4 µm to 4.2 µm, and the Haskeir laser from 4.5 µm to 12 µm. Both lasers can generate ~2 ps pulses at either 100 MHz or 200 MHz repetition rates with very low jitter.
The Auskerry laser uses a periodically poled lithium niobate (PPLN) non-linear crystal to generate near infrared light in the range of 1.4 um to 4.5 um. The Haskeir laser uses a different Orientation Patterned Gallium Phosphide (OP-GaP) non-linear crystal to generate mid-infrared light in the 4.5 um to 12 um range. Both lasers have been optimized to generate ~2 ps pulses with very high temporal fidelity allowing researchers to investigate the time domain behavior of detectors with high confidence.