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arXiv · 1510.08910

Active mode locking of quantum cascade lasers operating in external ring cavity

D. G. Revin·M. Hemingway·Y. Wang·J. W. Cockburn·A. Belyanin
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Abstract

Stable ultrashort light pulses and frequency combs generated by mode-locked lasers have many important applications including high-resolution spectroscopy, fast chemical detection and identification, studies of ultrafast processes, and laser metrology. While compact mode-locked lasers emitting in the visible and near infrared range have revolutionized photonic technologies, the systems operating in the mid-infrared range where most gases have their strong absorption lines, are bulky and expensive and rely on nonlinear frequency down-conversion. Quantum cascade lasers are the most powerful and versatile compact light sources in the mid-infrared range, yet achieving their mode locked operation remains a challenge despite dedicated effort. Here we report the first demonstration of active mode locking of an external-cavity quantum cascade laser. The laser operates in the mode-locked regime at room temperature and over the full dynamic range of injection currents of a standard commercial laser chip.

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D. G. Revin, M. Hemingway, Y. Wang, J. W. Cockburn, A. Belyanin. 2015-10-29. Active mode locking of quantum cascade lasers operating in external ring cavity. https://doi.org/10.1038/ncomms11440

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