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arXiv · 1507.08870

Dynamics of the Energy Relaxation in a Parabolic Quantum Well Laser

A. V. Trifonov·E. D. Cherotchenko·J. L. Carthy·I. V. Ignatiev·A. Tzimis·S. Tsintzos·Z. Hatzopoulos·P. G. Savvidis·A. V. Kavokin
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Abstract

We explore two parabolic quantum well (PQW) samples, with and without Bragg mirrors, in order to optimise the building blocks of a Bosonic Cascade Laser. The photoluminescence spectra of a PQW microcavity sample is compared against that of a conventional microcavity with embedded quantum wells (QWs) to demonstrate that the weak coupling lasing in a PQW sample can be achieved. The relaxation dynamics in a conventional QW microcavity and in the PQW microcavity was studied by a non-resonant pump-pump excitation method. Strong difference in the relaxation characteristics between the two samples was found. The semi-classical Boltzmann equations were adapted to reproduce the evolution of excitonic populations within the PQW as a function of the pump power and the output intensity evolution as a function of the pump-pump pulse delay. Fitting the PQW data confirms the anticipated cascade relaxation, paving the way for such a system to produce terahertz radiation.

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A. V. Trifonov, E. D. Cherotchenko, J. L. Carthy, I. V. Ignatiev, A. Tzimis, S. Tsintzos, Z. Hatzopoulos, P. G. Savvidis, A. V. Kavokin. 2015-07-31. Dynamics of the Energy Relaxation in a Parabolic Quantum Well Laser. https://doi.org/10.1103/physrevb.93.125304

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