Laser quantum cascade

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I. Howieson, E. Normand, M.T. McCulloch, Quantum-cascade lasers smell success. Laser Focus World, 41(3) S3... 

FIGURE 3.12 The layers of an active region of a quantum cascade laser. 

Fig. 21 Experimental setup for quantum cascade laser (QCL)-HWG gas sensing [92]...

Jerome Faist, Federico Capasso, Carlo Sirtori, Deborah L. Sivco, and Alfred Y. Cho, Quantum Cascade Lasers Federico Capasso, Carlo Sirtori, D. L. Sivco, and A. Y. Cho, Nonlinear Optics in Coupled-Quantum- Well Quasi-Molecules... 

Charlton C, Temelkuran B, Dellemann G, Mizaikoff B (2005) Midinfrared sensors meet nanotechnology Trace gas sensing with quantum cascade lasers inside photonic band-gap hollow waveguides. Appl Phys Lett 86 194102... 

Wojcik AK, Malara P, Blanchard R, Mansuripur TS, Capasso F, Belyanin A (2013) Gentsation of picosecond pulses and frequency combs in actively mode locked external ring cavity quantum cascade lasers. Appl Phys Lett 103... 

Kolhed M, Haberkorn M, Pustogov V, et al. (2002) Assessment of quantum cascade lasers as mid-infrared light sources for measurement of aqueous samples. Vibrational Spectroscopy 29 283-289. 

The quantum cascade laser is very different from the conventional semiconductor laser that has been described in this article, and is based on the intersubband transitions between the excited states of coupled quantum wells, or superlattice structures, and on the resonant tunneling between the wells as the pumping mechanism. This means that lasing action takes place between energy levels within the conduction band (not between the conduction and valance bands). More importantly, since the electron is still in the conduction band, novel bandgap engineering can provide for a transport mechanism that allows for this electron to be reinjected into another set of coupled quantum wells, and is therefore reused. As a result, one injected... 

New wavelengths will become available by utilizing strained layer semiconductor material and expanding on the idea of the quantum cascade laser. These new material structures will not only provide wavelengths previously unattainable from semiconductor injection lasers, but will undoubtedly imcover new physics resulting from the combined interaction of quantum structures and strained layer materials. 

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