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arXiv · 1812.05036

Square wave excitability in quantum dot lasers under optical injection

Michael Dillane·Bogalsaw Tykalewicz·David Goulding·Bruno Garbin·Stephane Barland·Bryan Kelleher
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Abstract

Quantum dot lasers display many unique dynamic phenomena when optically injected. Bistability has been predicted in a region of high injection strength. We show experimentally, rather than a phase-locked bistability, a square wave phenomenon is observed in this region. The squares can manifest as a periodic train but also as noise driven Type II excitable events. We interpret the appearance of the square waves as a thermally induced breaking of the bistability. Indeed we find experimentally that over the duration of a square the relative detuning between the master and the slave evolves deterministically. A relatively simple, physically motivated, rate equation model is presented and displays excellent agreement with the experiment.

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Michael Dillane, Bogalsaw Tykalewicz, David Goulding, Bruno Garbin, Stephane Barland, Bryan Kelleher. 2018-12-12. Square wave excitability in quantum dot lasers under optical injection. https://doi.org/10.1364/ol.44.000347

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