A Comparison of Amplitude-Phase Coupling and Linewidth Enhancement in Semiconductor Quantum- Well and Bulk Lasers
نویسنده
چکیده
The amplitude-phase coupling factor a (linewidth enhancement factor) is compared in typical semiconductor quantum-well and bulk double heterostructure lasers. As a direct consequence of the reduction of the differential gain, there is no reduction of a in the single quantum-well lasers compared to the bulk lasers. The number of quantum wells strongly affects the amplitude-phase coupling in quantum-well lasers. It is shown that the interband transition induced amplitude-phase coupling still dominates over that induced by the plasma effect of carriers in the typical quantum-well lasers. By considering the spontaneous emission factor in the spectral linewidth we show that there is an optimal quantum-well number for achieving the narrowest spectral linewidth.
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