Optical Quantum Random Number Generator

 APL Photonics paper "An optical chip for self-testing quantum random number generation" by  Nicolò Leone,  Davide Rusca,  Stefano Azzini,  Giorgio Fontana,  Fabio Acerbi,  Alberto Gola,  Alessandro Tontini, Nicola Massari,  Hugo Zbinden, and  Lorenzo Pavesi from University of Trento, FBK, and University of Geneva describes how photon shot noise-based RNG is built:

"We present an implementation of a semi-device-independent protocol of the generation of quantum random numbers in a fully integrated silicon chip. The system is based on a prepare-and-measure scheme, where we integrate a partially trusted source of photons and an untrusted single photon detector. The source is a silicon photomultiplier, which emits photons during the avalanche impact ionization process, while the detector is a single photon avalanche diode. The proposed protocol requires only a few and reasonable assumptions on the generated states. It is sufficient to measure the statistics of generation and detection in order to evaluate the min-entropy of the output sequence, conditioned on all possible classical side information. We demonstrate that this protocol, previously realized with a bulky laboratory setup, is totally applicable to a compact and fully integrated chip with an estimated throughput of 6 kHz of the certified quantum random bit rate."