Integrated system of an optical cryostat and single-photon detectors for applications in near infrared spectroscopy of quantum emitters

Historically, optical cryostats have not been able to reliably achieve temperatures below 4 K, a temperature that is higher than the operating threshold for many single photon detector designs. Instead, when performing single photon detection experiments, groups frequently require a secondary, fiber-coupled cryostat to hold the single photon detectors at their operating temperature. This is expensive in terms of purchasing equipment, space required, and upkeep costs.

We present measurements on quantum emitters that were taken in an optical cryostat with the capability to reach 1.7 K reliably. We integrated our superconducting nanowire single photon detectors directly into the sample chamber of the cryostat which eliminates the need for a secondary cryogenic system. This technique, developed with the help of industry partners, opens the door to off-the-shelf solid state quantum information systems, which will help accelerate solid state quantum information research.