Quantum detector tomography of superconducting nanostrip photon-number-resolving detector

Understand

Superconducting nanostrip photon detectors have been used as single photon detectors, which can discriminate only photons' presence or absence.

• It has recently been found that they can discriminate the number of photons by analyzing the output signal waveform, and they are expected to be used in various fields, especially in optical quantum information processing.
• Here, we improve the photon-number-resolving performance for light with a high-average photon number by pattern matching of the output signal waveform.
• Furthermore, we estimate the positive-operator-valued measure of the detector by a quantum detector tomography.