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arXiv · 1703.10036

Broadband monolithic extractor for metal-metal waveguide based terahertz quantum cascade laser frequency combs

Markus Rösch·Ileana-Cristina Benea-Chelmus·Christopher Bonzon·Martin J. Süess·Mattias Beck·Jérôme Faist·Giacomo Scalari
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Abstract

We present a monolithic solution to extract efficiently light from terahertz quantum cascade lasers with metal-metal waveguides suitable for broadband frequency comb applications. The design is optimized for a bandwidth of 500 GHz around a center frequency of 2.6 THz. A five-fold increase in total output power is observed compared to standard metal-metal waveguides. The extractor features a single-lobed far-field pattern and increases the frequency comb dynamical range to cover more than 50 % of the laser dynamic range. Frequency comb operation up to a spectral bandwidth of 670 GHz is achieved.

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Markus Rösch, Ileana-Cristina Benea-Chelmus, Christopher Bonzon, Martin J. Süess, Mattias Beck, Jérôme Faist, Giacomo Scalari. 2017-03-29. Broadband monolithic extractor for metal-metal waveguide based terahertz quantum cascade laser frequency combs. https://doi.org/10.1063/1.4993786

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