| Autor: |
Lingnau, Benjamin, Lüdge, Kathy, Chow, Weng W., Schöll, Eckehard |
| Rok vydání: |
2012 |
| Předmět: |
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| Zdroj: |
Physical Review E rapid comm. 86, 065201(2012) |
| Druh dokumentu: |
Working Paper |
| DOI: |
10.1103/PhysRevE.86.065201 |
| Popis: |
We show that the long-established concept of a linewidth-enhancement factor \alpha to describe carrier-induced refractive index changes in semiconductor lasers breaks down in quantum dot (QD) lasers when describing complex dynamic scenarios, found for example under high-excitation or optical injection. By comparing laser simulations using a constant \alpha-factor with results from a more complex non-equilibrium model that separately treats gain and refractive index dynamics, we examine the conditions under which an approximation of the amplitude-phase coupling by an \alpha-factor becomes invalid. The investigations show that while a quasi-equilibrium approach for conventional quantum well lasers is valid over a reasonable parameter range, allowing one to introduce an \alpha-factor as a constant parameter, the concept is in general not applicable to predict QD laser dynamics due to the different timescales of the involved scattering processes. |
| Databáze: |
arXiv |
| Externí odkaz: |
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