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arXiv · 1610.05721

Potential-inserted quantum well design for quantum cascade terahertz lasers

R. Benchamekh·J. -M. Jancu·P. Voisin
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Abstract

We report on a new design of terahertz quantum cascade laser based on a single, potential-inserted quantum well active region. The quantum well properties are engineered through single monolayer InAs inserts. The modeling is based on atomistic, spds* tight-binding calculations, and performances are compared to that of the classical three-well design. We obtain a 100% increase of the oscillator strength per unit length, while maintaining a high, nearly temperature-independent contrast between phonon-induced relaxation times of the upper and lower lasing states. The improved performances are expected to allow THz lasing at room temperature.

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R. Benchamekh, J. -M. Jancu, P. Voisin. 2016-11-14. Potential-inserted quantum well design for quantum cascade terahertz lasers. https://doi.org/10.1002/pssr.201600334

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