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arXiv · 1608.05257

Spectrally resolved far-fields of terahertz quantum cascade lasers

Martin Brandstetter·Sebastian Schönhuber·Michael Krall·Martin A. Kainz·Hermann Detz·Tobias Zederbauer·Aaron M. Andrews·Gottfried Strasser·Karl Unterrainer
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Abstract

We demonstrate a convenient and fast method to measure the spectrally resolved far-fields of multimode terahertz quantum cascade lasers by combining a microbolometer focal plane array with an FTIR spectrometer. Far-fields of fundamental TM0 and higher lateral order TM1 modes of multimode Fabry-P\'erot type lasers have been distinguished, which very well fit to the results obtained by a 3D finite-element simulation. Furthermore, multimode random laser cavities have been investigated, analyzing the contribution of each single laser mode to the total far-field. The presented method is thus an important tool to gain in-depth knowledge of the emission properties of multimode laser cavities at terahertz frequencies, which become increasingly important for future sensing applications.

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Martin Brandstetter, Sebastian Schönhuber, Michael Krall, Martin A. Kainz, Hermann Detz, Tobias Zederbauer, Aaron M. Andrews, Gottfried Strasser, Karl Unterrainer. 2016-08-18. Spectrally resolved far-fields of terahertz quantum cascade lasers. https://doi.org/10.1364/oe.24.025462

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