A scheme comparison of Autler-Townes based slow light in inhomogeneously broadened quantum dot media

We propose a method to achieve significant optical signal delays exploiting the effect of Autler-Townes splitting in an inhomogeneously broadened quantum dot medium. The absorption and slow-down effects are compared for three schemes i.e. $\Xi$, V and $\Lambda$, corresponding to different excitation configurations. Qualitative differences of the V-scheme compared to the $\Xi$- and $\Lambda$-scheme are found, which show that features of Autler-Townes splitting are only revealed in the V-scheme. The underlying physical mechanisms causing this discrepancy are analyzed and discussed. Finally we compare field propagation calculations of the schemes showing significantly larger achievable signal delays for the V-scheme despite finite absorption of the coupling field. This opens the possibility for using waveguide structures for both coupling and probe fields, thus significantly increasing the achievable signal delays

Analysis of timing jitter in external-cavity mode-locked semiconductor lasers

8 pages.-- Final full-text version available at: http://dx.doi.org/10.1109/JQE.2006.869808.We develop a comprehensive theoretical description of passive mode-locking in external-cavity mode-locked semiconductor lasers based on a fully-distributed time-domain approach. The model accounts for the dispersion of both gain and refractive index, nonlinear gain saturation from ultrafast processes, self-phase modulation, and spontaneous emission noise. Fluctuations of the mode-locked pulses are characterized from the fully-distributed model using direct integration of noise-skirts in the phase-noise spectrum and the soliton perturbations introduced by Haus. We implement the model in order to investigate the performance of a MQW buried heterostructure laser. Results from numerical simulations show that the optimum driving conditions for achieving the shortest pulses with minimum timing jitter occur for large reverse bias in the absorber section at an optimum optical bandwidth limited by Gordon-Haus jitter.This work was supported in part by the European project TOPRATE IST-2000-28657, Terabit/s Optical Transmission Systems based on Ultrahigh Channel Bitrate. The work of J. Mulet was supported in part by the Consejo Superior de Investigaciones Científicas of Spain through the program I3P-PC2003 and the Ministerio de Educación y Ciencia through the project CONOCE-2: FIS2004-00953