Numerical Studies of the Markovian Limit of the Quantum Kinetics with Phonon Scattering

✍ Scribed by M. Nedjalkov; I. Dimov; H. Haug

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 225 KB
• Volume: 209
• Category: Article
• ISSN: 0370-1972
• DOI: 10.1002/(sici)1521-3951(199809)209:1<109::aid-pssb109>3.0.co;2-s

✦ Synopsis

The contribution of the Markovian component of a quantum-kinetic model to the carrier dynamics in photoexcited semiconductors is studied for intermediate evolution times. It is shown that for zero lattice temperature two unphysical effects arise due to an exponential damping in the memory kernel, which results in the long-time limit in a Lorentz broadened energy delta function. A finite carrier density is observed in the semiclassically forbidden energy region. Also the carriers with energy below the LO phonon threshold are in mutual exchange, having a nonvanishing total outscattering rate. It is shown that in the inverse hyperbolic cosine damping model, which corrects the Lorentzian to an inverse hyperbolic cosine, such effects are suppressed. The results provided by the two models are obtained by a Monte Carlo algorithm based on the iteration approach and allowing one-dimensional simulation.