Nonlinear Dynamics in Semiconductor Lasers - Abstract
Erneux, Thomas
Quantum-dot (QD) and quantum cascade (QC) lasers are promising lasers for applications. QD lasers exhibit relaxation oscillations which are decaying faster than conventional quantum well lasers and QC lasers exhibit no relaxation oscillations at all. The objective of our work is to determine their stability properties when they are subject to an injected signal. We first consider a microscopically based five variables rate equations model for quantum dot lasers. In [1], we used asymptotic techniques and reduced the rate equations to three. The reduced equations allow for analytical studies. With C. Otto, we have continued the work started in [1] and obtained a full understanding on how the growth rates depend on the scattering rates. In particular, we show that if the scattering rates are sufficiently large, the relaxation oscillations disappear meaning that the decay towards the stable steady state is purely exponential. This is in agreement with recent numerical studies [2]. We then apply the same approach for the QD laser subject to injection [3]. Of particular physical interest is how the Hopf bifurcation boundary depends on the damping rate. We next consider a rate equation model for QC laser [4-6]. The QC laser subject to an injected signal has recently been theoretically investigated [7] The authors concluded that the optically injected QC laser is always stable. We show that is not necessary the case. The work is done in collaboration with F. Grillot, C. Sirtori, V. Kovanis, and A. Gavrielides. References 1. K. Lüdge, E. Schöll, E. A. Viktorov, and T. Erneux, J. Appl. Phys.109, 103112 (2011) 2. B. Lingnau, K. Lüdge, W.W. Chpw, and E. Schöll, submitted (2012) 3. J. Pausch, C. Otto, E. Tylaite, N. Majer, E. Schöll, K. Lüdge New J. Phys. 14, 053018 (2012) 4. T. Gensty, W. Elsäßer, and C. Mann, Opt. Exp. 13, 2032 (2005) 5. T. Gensty and W. Elsäßer, Opt. Comm. 256, 171 (2005) 6. Y. Petitjean, F. Destic, J.-C. Mollier, and C. Sirtori, J. Select. Topics in Quant. Electr. 17, 22 (2011) 7. Bo Meng and Qi Jie Wang, Optics Exp., 20, 1450 (2012)