title: Fast random bit generation with bandwidth-enhanced chaos in semiconductor lasers.
abstract: We experimentally demonstrate random bit generation using multi-bit samples of bandwidth-enhanced chaos in semiconductor lasers. Chaotic fluctuation of laser output is generated in a semiconductor laser with optical feedback and the chaotic output is injected into a second semiconductor laser to obtain a chaotic intensity signal with bandwidth enhanced up to 16 GHz. The chaotic signal is converted to an 8-bit digital signal by sampling with a digital oscilloscope at 12.5 Giga samples per second (GS/s). Random bits are generated by bitwise exclusive-OR operation on corresponding bits in samples of the chaotic signal and its time-delayed signal. Statistical tests verify the randomness of bit sequences obtained using 1 to 6 bits per sample, corresponding to fast random bit generation rates from 12.5 to 75 Gigabit per second (Gb/s) ( = 6 bit x 12.5 GS/s).
authors.affiliation: Department of Electronics and Computer Systems, Takushoku University, 815-1 Tatemachi, Hachioji, Tokyo 193-0985, Japan.
authors.forename: Kunihito
authors.initials: K
authors.lastname: Hirano
authors.forename: Taiki
authors.initials: T
authors.lastname: Yamazaki
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Morikatsu
authors.forename: Haruka
authors.initials: H
authors.lastname: Okumura
authors.forename: Hiroki
authors.initials: H
authors.lastname: Aida
authors.forename: Atsushi
authors.initials: A
authors.lastname: Uchida
authors.forename: Shigeru
authors.initials: S
authors.lastname: Yoshimori
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Yoshimura
authors.forename: Takahisa
authors.initials: T
authors.lastname: Harayama
authors.forename: Peter
authors.initials: P
authors.lastname: Davis
mesh_terms: D003198:Computer Simulation; D054023:Lasers, Semiconductor; D015233:Models, Statistical; D017711:Nonlinear Dynamics; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*