Single-photon metrology

Anish Mahavir Bhargav, Abdul Wahid, Samaresh Das +1 more

Sergey A. Magnitskii, Dmitry N. Frolovtsev, D. P. Agapov +3 more

Shigeki Takeuchi

Thomas Gerrits

We will present our current efforts on single photon quantum metrology using high-efficiency superconducting detectors and high-efficiency single-photon sources based on spontaneous parametric downconversion. Optical power measurements based on single photon counting could establish a quantum standard for optical power calibration in the future. At NIST we are pursuing the development of single photon sources and single photon detectors for metrology, quantum and classical applications. As part of these efforts, we are pursuing the establishment of a measurement service for the calibration of single photon detectors. We present how our calibration is tied to the calibration of our transfer standard optical fiber power meters. Using the beamsplitter method, we have implemented a fiber-coupled and free-space measurement system. Also, we have developed testbeds and measurement protocols for the characterization of single photon sources and single photon detectors. We will review several methods, which allow for the characterization of the spatial and spectral degree of freedom in spontaneous parametric downconversion.

Ashley Lyons

Keith R. Motes, Jonathan P. Olson, Evan J. Rabeaux +3 more

We show that a passive, linear-optical interferometer (fed with only single-photon inputs and utilizing single-mode photodetection) is capable of beating the shotnoise limit, providing a potential pathway forward to practical quantum metrology.