Parametric Study of Chaotic Combs for High-Rate Random Number Generation

Ultrafast physical random bit generators (RBGs) underpin numerous critical applications, from secure communications to computational simulations. Microresonator-based frequency combs in a chaotic state have emerged as a promising source of high-speed random bit sequences, as each comb tooth acts as an independent random bit source. This letter presents the effect of different chaotic comb characteristics on the RBG rate. A parametric study based on the Lugiato-Lefever Equation (LLE) has been implemented to study the effect of RF bandwidth, optical bandwidth (depending on the pump power and linewidth of a microresonator), and sampling rate on the generation rate. By analyzing these results, we establish guidelines for choosing the comb parameters that maximize bit generation rates.