Quantum Entropy Model of an Integrated Quantum-Random-Number-Generator Chip

We present the physical model for the entropy source of a quantum-random-number-generator chip based on the quantum fluctuations of the photon number emitted by light-emitting diodes. This model, combined with a characterization of the chip, estimates a quantum min-entropy of over 0.98 per bit without postprocessing. Finally, we show with our model that the performances in terms of security are robust against fluctuations over time.