Extending single-photon detection capabilities into the mid- infrared is expected to have far-reaching implications for long-wavelength quantum optics, quantum and free-space communication, astronomy, environmental monitoring, and fundamental molecular sciences. We showcase the development of short-wave infrared (2.2-2.3 µm) and mid- wave infrared (3.0 µm) superconducting nanowire single-photon detectors (SNSPDs). In both wavelength ranges, we venture beyond state-of-the-art and achieve the best-reported system detection efficiencies and specific detectivity. We discuss the challenges in cryogenics, optics, and SNSPD design and use our mid-infrared single-photon detection to characterize emerging materials platforms and quantum emitters in a previously unattainable manner.
Oksenberg et al. (2025) studied this question.