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PACS:05.45.−a, 42.65.−k, 42.65.Sf ; We introduce a new class of excitable systems with two-dimensional fast dynamics that includes inertia. A novel transition from excitability to relaxation oscillations is discovered where the usual Hopf bifurcation is followed by a cascade of period doubled and chaotic small excitable attractors and, as they grow, by a new type of canard explosion where a small chaotic background erratically but deterministically triggers excitable spikes. This scenario is also found in a model for a nonlinear Fabry-Perot cavity with one pendular mirror. ; This work was partially funded by the European Union ILIAS Project (No. RII3-CT-2003-506222), the CSIC— Spain Grant HIELOCRIS (No. 200530F0052). ; Peer reviewed

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7 pages, 5 figures. ; We present an analytical, numerical and experimental study of the switching time and jitter of current induced polarization switching in Vertical-Cavity Surface-Emitting Lasers in the presence of spontaneous emission noise. Assuming that the switching is induced by changes in the dichroism, the problem can be reduced to the well-known first passage time problem in gain switched Class-A lasers. The theoretical results obtained in this way show excellent agreement both with numerical simulations based on the full rate equations model, and with experiments performed on oxide-confined Vertical-Cavity Surface-Emitting Lasers. ; This work was supported in part by the Belgian government under the Interuniversity Attraction Pole program (IAP V/18), in part by the Concerted Research Action, and in part by the Research Council of the Vrije Universiteit Brussel. The collaboration between the groups in Brussels, Palma de Mallorca, Ulm, and Florence was made possible through the European RTN network VISTA under Contract HPRN-CT-2000-00034. Additional support from, and discussions within, the framework of the European COST actions 268 and 288 are acknowledged. The work of J. Danckaert, G. Verschaffelt, and B. Nagler was supported by the Fund for Scientific Research—Flanders. ; Peer reviewed