Photon Spot Inc.

Photon Spot manufactures sub-Kelvin cryogenic systems and superconducting nanowire single-photon detectors (SNSPDs) for top research groups around the world.

The company’s SNSPDs exhibit ultra-low dark counts, sub-100 ps jitter and >90% quantum efficiency near 1550 nm. Its detectors are used for free-space optical communication, quantum optics experiments and linear optics quantum computing. Photon Spot’s fully automated, closed-cycle cryostats use a helium sorption fridge to provide temperatures below 1 K (-272 °C, -457 °F).

The company’s cryostats are a cost-effective alternative to ADRs or dilution fridges, getting to 800 mK with helium-4 and 400 mK with helium-3. Its cryostats can house up to 64 SNSPDs (each with individual fibers, coaxes and electronics) or a detector array with free-space optical access and vibration-reducing fixtures.

Photon Spot also manufactures cryostats that offer very low temperature oscillations (~3 mK at 4 K with a 500 mW load). These cryostats are used for cooling down Josephson junction arrays for quantum-based voltage standards.