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: 3.49). 02/2012; 20(4):4297-308. DOI: 10.1364/OE.20.004297
Source: PubMed


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.

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Available from: Jian Z Zhang, Dec 29, 2013
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    • "As an example, the time delay is susceptible to detection by Eve [19]–[25]. Semiconductor lasers subject to optical feedback are commonly employed to generate chaotic signals for potential applications in chaos-based communications [12], key exchange [9], random bit generation [26]–[30], and so on. Recently , it has been shown that the time delay signature in chaotic lasers can be easily extracted by using statistics approaches, such as autocorrelation function (ACF) and delayed mutual information (DMI) [31]–[34]. "
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