Fast random bit generation based on a single chaotic semiconductor ring laser

摘要

Random numbers are useful for a wide variety of applications including encryption and authentication protocols, stochastic modeling, and online gaming and lotteries. Typically, they can be generated with improved bit rates from chaotic signals by making use of post-processing methods including multi-bit extraction or bitwise OR-Exclusive (XOR) operations. The latter requires two distinct chaotic signals which are typically generated using two separated devices, e.g. two Fabry-Perot lasers. Here, we numerically and experimentally demonstrate that, by combining these two post-processing methods in a single chaotic semiconductor ring laser (SRL), it is possible to generate true random bits with a bit rate up to 40 Gb/s from a chaos bandwidth of ≈ 2 GHz, thanks to the device ability of lasing in two directional modes and the fact that the two mode signals have low correlations. In addition, SRLs can be easily implemented on chip.