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arXiv · 1605.09416

Distributed feedback terahertz frequency quantum cascade lasers with dual periodicity gratings

F. Castellano·S. Zanotto·L. H. Li·A. Pitanti·A. Tredicucci·E. H. Linfield·A. G. Davies·M. S. Vitiello
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Abstract

We have developed terahertz frequency quantum cascade lasers that exploit a double-periodicity distributed feedback grating to control the emission frequency and the output beam direction independently. The spatial refractive index modulation of the gratings necessary to provide optical feedback at a fixed frequency and, simultaneously, a far-field emission pattern centered at controlled angles, was designed through use of an appropriate wavevector scattering model. Single mode THz emission at angles tuned by design between 0° and 50° was realized, leading to an original phase-matching approach, lithographically independent, for highly collimated THz QCLs.

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F. Castellano, S. Zanotto, L. H. Li, A. Pitanti, A. Tredicucci, E. H. Linfield, A. G. Davies, M. S. Vitiello. 2016-05-30. Distributed feedback terahertz frequency quantum cascade lasers with dual periodicity gratings. https://doi.org/10.1063/1.4905338

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