Single-Photon Generation and Detection

Per Jönsson

Heping Zeng, Guang Wu, E Wu +4 more

Yan Liang, Heping Zeng

Xingjian Li, Jianyong Hu, Bingkun Wang +9 more

Quantum random number generators (QRNGs) can generate true random numbers and have significant applications in quantum communication, numerical computation, and model simulation. However, the rate of random number generation based on photon detection is constrained by the maximum count rate of a single-photon detector. Therefore, improving the efficiency of random number generation for individual photon detection events becomes an optional way to increase the rate of random number generation. In this paper, multidimensional photon detection is implemented to enhance single-photon detection events, thereby providing a new, to the best of our knowledge, technical development strategy for high-speed random number generators. The temporal and spatial coherence of coherent-state photons is utilized as a valuable quantum resource, enabling us to achieve the simultaneous extraction of time-space measurement collapsed randomness for single-photon detection events using a chip-scale CMOS-integrated single-photon avalanche diode array. The efficiency of random number generation for single-photon detection events is effectively improved. In our experiments, up to 20 bits can be extracted from an individual photon detection event, and the rate of random number generation reaches up to 2.067 Gbps.

Kazuyuki Kuroyama, Marcus Larsson, Sadashige Matsuo +6 more

We demonstrate paired generation of a single photo-electron in a quantum dot and a single photon from a single polarization-entangled photon pair that is generated by spontaneous parametric down conversion. The electron is reated in a GaAs quantum dot via inter-band resonantexcitation by irradiating one of the paired photons on the dot, while the remaining photon is detected by a single photon counter. Because the paired photons are generated simultaneously, the photo-electron and the remaining photon should be observed as a coincident event if the traveling distance is equivalent between them. The coincidence is probabilistic due to the probabilistic generation of the paired photon. We observe the probability of finding the photon with the photo-electron detection substantially higher then that without the photo-electron detection and derive the coincident rate comparable to the emission rate of the original photon pairs.

Oliver Graydon