Optical external efficiency of terahertz quantum cascade laser based on Čerenkov difference frequency generation

A. Hamadou (1) , Jean-Luc Thobel (2, 3) , S. Lamari (4)

1 Département de génie civil, Faculté des Sciences et de la Technologie, Université Mohamed Elbachir Elibrahimi
2 IEMN - Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520
3 SILPHYDE - IEMN - SImuLation PHYsique de Dispositifs Electroniques et opto-electroniques - IEMN
4 L.E.S.I.M.S., Département de Physique

In this paper, we consider terahertz sources based on Čerenkov difference frequency generation in a dual-wavelength mid-infrared quantum cascade laser and calculate analytically the optical external efficiency of the out-going terahertz wave. The mid-infrared pumps operate simultaneously and have a common upper level. For short cavity lengths and low terahertz losses in the substrate, we find that implementation of the Čerenkov emission scheme in terahertz difference frequency generation quantum cascade lasers improves the optical external efficiency dramatically. The maximum value of the latter is close to 19%, but is only attainable if the laser exhibits negligible mid-infrared transmission losses.

Mots clés: Terahertz quantum cascade laser; difference frequency generation; optical external efficiency; Čerenkov; phased matching

Domaines: Micro et nanotechnologies/Microélectronique; Matière Condensée [cond-mat]

A. Hamadou, Jean-Luc Thobel, S. Lamari. Optical external efficiency of terahertz quantum cascade laser based on Čerenkov difference frequency generation. Journal of Nonlinear Optical Physics and Materials, 2019, 28 (04), pp.1950036. ⟨10.1142/S021886351950036X⟩. ⟨hal-02976827⟩