Optical scattering enhances randomness characteristics, increases the chaotic behavior of coherent sources, broadens the distribution of photon statistics and makes it super-Poissonian which allows faster sampling compared to Poissonian.
Abstract The speed of quantum random number generators (QRNGs) is a major concern for practical applications. In this work, we introduce scattering as a method to enhance the randomness characteristics of the entropy source. This method allows optical bit extraction with a faster sampling rate without compromising the randomness quality compared to the coherent source based balanced homodyne detection. Scattering is a probabilistic phenomenon which increases the chaotic behaviour of coherent sources. It broadens the distribution of photon statistics and makes it super-Poissonian. We show that a signal with super-Poissonian distribution has better randomness compared to a Poissonian one, indicated by their autocorrelation characteristics and the randomness test results. The use of scattering mechanisms as an entropy source eases the miniaturization of QRNGs, it also makes them compatible and adaptable to existing technologies.
The speed of quantum random number generators is a major concern for practical quantum applications. However, the bit extraction process limits the final bit rate due to lack of comparably fast electronics. Here we introduce optical scattering as a method to perform optical bit extraction. Scattering is a probabilistic phenomenon and it increases the chaotic behaviour of coherent sources. As a result, it broadens the distribution of photon statistics and makes it super-Poissonian. We show that the raw signal of the sources with super-Poissonian distribution have better randomness compared to Poissonian, indicated by their autocorrelation characteristics. Therefore, the optical bit extraction process allows faster sampling of raw signal without compromising the randomness quality. The use of scattering mechanisms as an entropy source eases the miniaturization of quantum random number generators, it also makes them compatible and adaptable to existing technologies.
The importance of quantum random number generators (QRNGs) is increasing day by day. An important aspect of any QRNG is the speed of the system. This paper introduces the theory behind a pseudothermal light based QRNG. This pseudothermal effect is provided by using an optical scatterer in the setup. Pseudothermal light is used as the local oscillator of the system instead of a conventional coherent or thermal light source where the pseudothermal light combines the advantages of both sources. This technique converts the Poissonian distribution of light to super-Poissonian to have better randomness characteristics and allow a faster bit generation rate.