Dynamic filamentation and beam quality of quantum-dot lasers
نویسندگان
چکیده
We present a comparative study of numerical simulations and experiments on the spatiotemporal dynamics and emission characteristics of quantum-well and quantum-dot lasers of identical structure. They show that, in the quantum-dot laser, the strong localization of carrier inversion and the small amplitude–phase coupling enable a significant improvement of beam quality compared to quantum-well lasers of identical geometry. Near-field profiles and beam quality (M ) parameters calculated on the basis of time-dependent effective Maxwell–Bloch equations into which the physical properties of the active media are included via space-dependent material parameters, effective time constants, and matrix elements are fully confirmed by experimental measurements. Together they indicate that, in the quantum-dot laser, the strong localization of carrier inversion and the small amplitude–phase coupling enable a significant improvement of beam quality compared with quantum-well lasers of identical geometry. © 2004 American Institute of Physics. @DOI: 10.1063/1.1668330#
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