Phase-modulated dual-path feedback for time delay signature suppression from intensity and phase chaos in semiconductor laser

Wideband complex-enhanced chaos generation using a semiconductor laser subject to delay-interfered self-phase-modulated feedback

“…On the other hand, since the conventional feedback light is a linear replica of the laser output, the external cavity resonation introduces a periodicity in the chaos, which results in an obvious time delay signature (TDS) that indicates the feedback delay time of the external cavity. The TDS can be easily identified by several methods, such as the calculations of autocorrelation function (ACF), digital mutual information (DMI), and permutation entropy (PE) [18][19][20][21]. The obvious TDS degrades the randomness of RBG, threats the privacy of chaos sources in secure communication applications, and degrades the precision of chaotic radar.…”

Time-delay signatures hidden in the phase of chaotic output of mutually delay-coupled vertical-cavity surface-emitting lasers

“…In 2011, Nguimdo et al first indicated that the phase time series could also be utilized to retrieve TDS (corresponding TDS is named as P-TDS) in a single external cavity feedback DFB-SL chaotic system, and they found that the TDS well concealed Contents lists available at ScienceDirect journal homepage: www.elsevier.com/locate/optcom in the intensity time series may still be retrieved successfully based on the phase time series [29]. Since then, the characteristics of P-TDS in diverse DFB-SL based chaotic systems have been reported successively [30][31][32]. Nguimdo et al reported the characteristics of P-TDS in a ring laser chaotic system [30].…”

“…Nguimdo et al reported the characteristics of P-TDS in a ring laser chaotic system [30]. Xiang et al investigated numerically the evolutions of P-TDS in a dual-path optical injection DFB-SL chaotic system [31] and a phase-modulated dual-path feedback DFB-SL chaotic system [32]. However, related investigations on the P-TDS are almost focused on the chaotic system based on DFBSLs, and pay little attention on VCSELs-based chaotic systems.…”

Period-one characteristic in an optoelectronic delayed feedback semiconductor laser and its application in sensing

“…Semiconductor lasers can exhibit instability behaviors when additional freedoms are introduced to the lasers. A semiconductor laser due to optical feedback or external injection light can generate an unstable or a chaotic pulse [1][2][3][4] . Compared to these lasers, an optoelectronic laser system is much more reliable and flexible using electrical control [5][6][7][8] .…”

“…Dynamics in the optoelectronic feedback laser is described as a function of the feedback level, where the subsequent text lists the laser parameters. Results are summarized, where we find four zones, namely: (1) stable zones, the dynamics in the system shifts to reach a stable state; (2) undamped relaxation oscillations zones, where the laser shows stochastic fluctuations after period-one and period-three behaviors [3][4][5] ; (3) self-pulsation zones, where the behavior of the laser oscillates periodically; these zones will be used in the context of sensing reference regimes where we find that a small injection into the laser results in an obvious diversification away from the periodone state; (4) period-three zones, where the laser output shows three series of pulses. The distributions of the found zones are different from those of the other systems [5][6][7][8][9] .…”