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An all-optical configuration for double-sideband suppressed-carrier modulation of an injection-locked semiconductor laser is presented. The absence of a strong carrier component permits the amplification of the information-carrying sidebands immediately following the modulation and therefore preserve the high signal-to-noise ratio throughout the system. This shows explicitly that the injection-induced modulation of the optical phase essentially sets the dynamic response required of the locked laser.

We study the response diagram of the bistable iodate–arsenous acid reaction and investigate analytically and experimentally the jump transitions due to a time-dependent parameter. This parameter is changed linearly in time and its rate of change is characterized by a dimensionless parameter ε. We observe that the jump transition does not occur at a limit point of the steady states but is delayed. Asymptotic studies predict that this delay is proportional to an O(ε2/3) quantity as ε→0. The ε2/3 law is in agreement with the experimental observations of the transition between the lower and upper branches of steady states even if ε is not a small quantity [T. Erneux and J. P. Laplante, J. Chem. Phys. 90, 6129 (1989)]. In this paper, we investigate experimentally the second transition of the iodate–arsenous acid reaction, namely, the transition between the upper and lower branches of the steady states. We have found that the delay does not satisfy the ε2/3 law but rather is following an ε law. By comparing the experimental results and the results obtained from an analytical and numerical study of the bistable reaction, we show that the values of ε used in the experiments are too large to follow the ε2/3 law. [ABSTRACT FROM AUTHOR]

Bifurcation or limit point problems with slowly varying parameters are of interest in many research areas. Typically, the time dependency of the bifurcation parameter introduces a delay in the transition from one type of solution to the other. In this article, we study both theoretically and experimentally the bistable iodate–arsenous acid reaction when subjected to a time-dependent bifurcation parameter. This problem is tractable analytically and allows us to derive an expression for the transition delay with respect to the static bifurcation point as a function of the dimensionless ramping rate ε. For small and moderate values of ε, we predict that the delay is proportional to εp where the exponent p=2/3approx. 0.67. For the experimental conditions considered in this paper, our experimental data yield p=0.63±0.10. [ABSTRACT FROM AUTHOR]