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220 fs Er-Yb:glass laser mode-locked by a broadband low-loss Si/Ge saturable absorber

F. J. Grawert·S. Akiyama·F. O. Ilday·J. Liu·J. T. Gopinath·H. M. Shen·K. Wada·E. P. Ippen·L. C. Kimerling·F. X. Kaertner
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Abstract

We demonstrate femtosecond performance of an ultra-broadband high-index-contrast saturable Bragg reflector consisting of a silicon/silicon-dioxide/germanium structure that is fully compatible with CMOS processing. This device offers a reflectivity bandwidth of over 700 nm and sub-picosecond recovery time of the saturable loss. It is used to achieve mode-locking of an Er-Yb:glass laser centered at 1540 nm, generating 220 fs pulses, with the broadest output spectrum to date.

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F. J. Grawert, S. Akiyama, F. O. Ilday, J. Liu, J. T. Gopinath, H. M. Shen, K. Wada, E. P. Ippen, L. C. Kimerling, F. X. Kaertner. 2004-11-25. 220 fs Er-Yb:glass laser mode-locked by a broadband low-loss Si/Ge saturable absorber. https://doi.org/10.1364/ol.30.000329

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