Article

Direct generation of all-optical random numbers from optical pulse amplitude chaos

Institute of Optoelectronic Engineering, College of Physics and Optoelectronics, Taiyuan University of Technology, Taiyuan 030024, China.
Optics Express (Impact Factor: 3.53). 02/2012; 20(4):4297-308. DOI: 10.1364/OE.20.004297
Source: PubMed

ABSTRACT We propose and theoretically demonstrate an all-optical method for directly generating all-optical random numbers from pulse amplitude chaos produced by a mode-locked fiber ring laser. Under an appropriate pump intensity, the mode-locked laser can experience a quasi-periodic route to chaos. Such a chaos consists of a stream of pulses with a fixed repetition frequency but random intensities. In this method, we do not require sampling procedure and external triggered clocks but directly quantize the chaotic pulses stream into random number sequence via an all-optical flip-flop. Moreover, our simulation results show that the pulse amplitude chaos has no periodicity and possesses a highly symmetric distribution of amplitude. Thus, in theory, the obtained random number sequence without post-processing has a high-quality randomness verified by industry-standard statistical tests.

0 Bookmarks
 · 
139 Views
  • [Show abstract] [Hide abstract]
    ABSTRACT: Phase-modulated dual-path feedback (PM-DPF) is proposed to conceal time delay (TD) signatures from both intensity chaos and phase chaos in semiconductor lasers (SLs). The TD signatures are evaluated via both auto-correlation function and permutation entropy function. For the purpose of comparison, we also consider three other feedback configurations: SL with single-path feedback (SPF), SL with phase-modulated single-path feedback (PM-SPF), and SL with dual-path feedback (DPF). It is found that, for four feedback configurations, under the condition of strong feedback, successful TD concealment from both intensity and phase chaos can only be realized in SL with PM-DPF, due to the joint contribution of dual path feedback structure and phase modulation. Furthermore, to check the key factor contributing to TD concealment in SL with PM-DPF, the effects of feedback strength, feedback delay, modulation depth and modulation frequency are examined carefully. It is shown that, to obtain successful TD concealment from both intensity and phase chaos under the condition of strong feedback, the modulation frequency close to or greater than the relaxation oscillation frequency is suggested, while the modulation depth is the most important factor contributing to TD concealment, and higher modulation depth is desired. Besides, similar feedback strengths for two feedback paths are suggested. The TD signatures of intensity chaos for SLs with different feedback configurations are also verified experimentally. The SL with PM-DPF is an excellent chaotic source for security-enhanced chaotic communication systems as well as random number of generators based on chaotic SLs.
    Optics Communications 08/2014; 324:38–46. DOI:10.1016/j.optcom.2014.03.017 · 1.54 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We generate random bit sequences from chaotic temporal waveforms by using photonic integrated circuits (PICs) with different external cavity lengths. We investigate the condition for generating random bits at different sampling rates of single-bit generation method with the PICs. We succeed in generating certified random bit sequences by using the PIC with 3, 4, 5, or 10-mm-long external cavity, whereas random bits cannot pass all the statistical tests of randomness when the PIC with 1 or 2 mm-long external cavity is used.
    Optics Express 05/2014; 22(10):11727-11740. DOI:10.1364/OE.22.011727 · 3.53 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The continuous-wave output of a single-mode erbium-doped fibre ring laser when subjected to cavity-loss modulation is found to exhibit linear as well as nonlinear resonances. At sufficiently low driving amplitude, the system resembles a linear damped oscillator. At higher amplitudes, the dynamical study of these resonances shows that the behaviour of the system exhibits features of a nonlinear damped oscillator under harmonic modulation. These nonlinear dynamical features, including harmonic and subharmonic resonances, have been studied experimentally and analysed with the help of a simple time-domain and frequency-domain information obtained from the output of the laser. All the studies are restricted to the modulation frequency lying in a regime near the relaxation oscillation frequency.
    Pramana 07/2014; 83(1):147-159. DOI:10.1007/s12043-014-0770-1 · 0.72 Impact Factor

Full-text (2 Sources)

Download
19 Downloads
Available from
May 22, 2014