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arXiv · 0903.4385

Stable mode-locked pulses from mid-infrared semiconductor lasers

Christine Y. Wang·L. Kuznetsova·V. M. Gkortsas·L. Diehl·F. X. Kaertner·M. A. Belkin·A. Belyanin·X. Li·D. Ham·H Schneider·P. Grant·C. Y. Song·S. Haffouz·Z. R. Wasilewski·H. C. Liu·Federico Capasso
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Abstract

We report the unequivocal demonstration of mid-infrared mode-locked pulses from a semiconductor laser. The train of short pulses was generated by actively modulating the current and hence the optical gain in a small section of an edge-emitting quantum cascade laser (QCL). Pulses with pulse duration at full-width-at-half-maximum of about 3 ps and energy of 0.5 pJ were characterized using a second-order interferometric autocorrelation technique based on a nonlinear quantum well infrared photodetector. The mode-locking dynamics in the QCLs was modelled and simulated based on Maxwell-Bloch equations in an open two-level system. We anticipate our results to be a significant step toward a compact, electrically-pumped source generating ultrashort light pulses in the mid-infrared and terahertz spectral ranges.

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Christine Y. Wang, L. Kuznetsova, V. M. Gkortsas, L. Diehl, F. X. Kaertner, M. A. Belkin, A. Belyanin, X. Li, D. Ham, H Schneider, P. Grant, C. Y. Song, S. Haffouz, Z. R. Wasilewski, H. C. Liu, Federico Capasso. 2009-03-25. Stable mode-locked pulses from mid-infrared semiconductor lasers. https://doi.org/10.1364/oe.17.012929

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