A High Speed, Post-Processing Free, Quantum Random Number Generator

A quantum random number generator (QRNG) based on gated single photon detection of an In–GaAs photodiode at gigahertz frequency is demonstrated. Owing to the extremely long coherence time of each photon, each photons’ wave function extends over many gating cycles of the photodiode. The collapse of the photon wave function on random gating cycles as well as photon random arrival time detection events are used to generate sequences of random bits at a rate of 4.01Mbit∕s. Importantly, the random outputs are intrinsically biasfree and require no postprocessing procedure to pass random number statistical tests, making this QRNG an extremely simple device.