The role of plasma cooling, heating and memory effects in sub-picosecond pulse propagation in semiconductor amplifiers

R. A. Indik, M. Mlejnek, J.V. Moloney
Arizona Center for Mathematical Sciences, Department of Mathematics
University of Arizona, Tucson, AZ 85721
R. Binder
Optical Sciences Center
University of Arizona, Tucson, AZ 85721
S. Hughes, A. Knorr, S.W. Koch
Fachbereich Physik und Zentrum für Materialwissenschaften
Phillips-Universität, Renthof 5, D-35032 Marburg (FRG)

Abstract:

Based on a microscopic theory of a two-band semiconductor light-amplifier, we show that plasma heating, cooling and ultrafast memory effects all act in concert to produce strong distortion of sub-picosecond pulses propagating in semiconductor amplifiers. Plasma heating, spectral hole burning and carrier density depletion are responsible for saturation of the gain seen by a propagating intense femtosecond pulse in the amplifier. Plasma cooling replenishes the carrier population on the trailing edge of the pulse, leading to pulse broadening as a consequence of gain regeneration. The inclusion of memory effects in the description of dephasing processes goes beyond the usual Markov assumption of constant dephasing rates; it significantly affects the dynamical pulse reshaping processes.

• Introduction
• Theoretical Basis
• Plasma cooling induced pulse reshaping
• Memory effects
• Summary
• Acknowledgments
• References
• About this document ...

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