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arXiv · 0709.0594

Transient quantum evolution of 2D electrons under photoexcitation of a deep center

F. T. Vasko·A. Hernandez-Cabrera·P. Aceituno
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Abstract

We have considered the ballistic propagation of the 2D electron Wigner distribution, which is excited by an ultrashort optical pulse from a short-range impurity into the first quantized subband of a selectively-doped heterostructure with high mobility. Transient ionization of a deep local state into a continuum conduction c-band state is described. Since the quantum nature of the photoexcitation, the Wigner distribution over 2D plane appears to be an alternating-sign function. Due to a negative contribution to the Wigner function, the mean values (concentration, energy, and flow) demonstrate an oscillating transient evolution in contrast to the diffusive classical regime of propagation.

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F. T. Vasko, A. Hernandez-Cabrera, P. Aceituno. 2007-09-05. Transient quantum evolution of 2D electrons under photoexcitation of a deep center. https://doi.org/10.1103/physrevb.77.075310

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