Throwing dice really fast

The rapid generation of random numbers or bits, called random bit generation (RBG) with a speed of 12.5 Gbit/s is based on sampling the chaotic intensity fluctuations of a semiconductor laser with time delayed optical feedback. The thresholding requirement in the process is eliminated by taking the derivative of the digitized signal, which forms a highly symmetric, temporally stable and smooth distribution that can therefore be evenly divided into an unbiased sequence. The techniques makes it possible to generated sequences as long as a few Gbit at an overall bit rate of 12.5 Gbit/s. The nonlinearity of the analog-to-digital converter introduces a measurable bias that can be eliminated by periodically inverting the generated bit sequence that enables to generate the arbitrarily long sequences at the 12.5-Gbit/s rate.