Dynamic amplitude-phase coupling in quantum-dot lasers

Dynamic amplitude-phase coupling in quantum-dot lasers

The well-known a-factor is a convenient measure to describe the magnitude of the amplitude-phase coupling of semiconductor lasers. But is the a-factor really a parameter? First-principle simulations of InGaAs quantum-dot lasers and amplifiers show that in spatially extended quantum-dot laser structures, the amplitude phase coupling is far from being a constant. Our computation of the a-factor d...

Phase-amplitude coupling characteristics in directly modulated quantum dot lasers

A Comparison of Amplitude-Phase Coupling and Linewidth Enhancement in Semiconductor Quantum- Well and Bulk Lasers

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 quan...

Dynamic filamentation and beam quality of quantum-dot lasers

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 la...

Analytic Characterization of the Dynamic Regimes of Quantum-Dot Lasers

We present analytic treatment of the three different dynamic regimes found in quantum-dot laser turn-on and modulation dynamics. A dynamic coupling, and thus density-dependent scattering lifetimes between dots and reservoir, are identified to be crucial for a realistic modeling. We derive a minimal model for the quantum-dot laser dynamics that can be seeded with experimentally accessible parame...