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Wave engineering with THz quantum cascade lasers

Nature Photonics volume 7, pages 691–701 (2013)Cite this article

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Abstract

Quantum cascade lasers are compact devices based on mature compound semiconductors such as GaAs that take advantage of highly developed optoelectronic fabrication techniques to integrate linear and nonlinear functions. This Review discusses terahertz-wave engineering using quantum cascade lasers with a particular focus on techniques that have been implemented to control their spectral and output beam properties. After briefly introducing the types of active regions and surveying present maximum operating temperatures, we review several photonic structures used for frequency and beam engineering, ranging from distributed feedback lasers to photonic crystals. We then describe techniques that allow the upconversion of terahertz quantum cascade laser radiation in the near-infrared region using nonlinear intracavity mixing. Finally, we review frequency stabilization of terahertz quantum cascade lasers with a special emphasis on phase locking to near-infrared frequency combs.

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Figure 1: Maximum operating temperatures of THz QCLs reported to date for pulsed mode operation.
Figure 2: DFB THz QCLs and MEMS-based device for wideband frequency tuning.
Figure 3: THz QCLs based on third-order DFB gratings and photonic crystals.
Figure 4: Photonic-crystal structures for high power extraction.
Figure 5: Nonlinear mixing of THz QCLs with near-infrared radiation.
Figure 6: Generation of a beat-note signal between a THz QCL and a femtosecond-laser comb.
Figure 7: Phase-locking of THz QCLs to electronic multipliers and femtosecond-laser combs.

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Acknowledgements

The authors acknowledge several helpful discussions with S. Dhillon and G. Xu. C.S. gratefully acknowledges support from the Institut Universitaire de France.

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  1. Laboratoire Matériaux et Phénomènes Quantiques, Université Paris Diderot and CNRS, UMR7162, Paris, 75205, France

    Carlo Sirtori & Stefano Barbieri

  2. Institut d'Electronique Fondamentale, Université Paris Sud and CNRS, UMR8622, Orsay, 91405, France

    Raffaele Colombelli

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Sirtori, C., Barbieri, S. & Colombelli, R. Wave engineering with THz quantum cascade lasers. Nature Photon 7, 691–701 (2013). https://doi.org/10.1038/nphoton.2013.208

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