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arXiv · 0707.2423

WKB Propagation of Gaussian Wavepackets

Raphael N. P. Maia·Fernando Nicacio·Raul O. Vallejos·Fabricio Toscano
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Abstract

We analyze the semiclassical evolution of Gaussian wavepackets in chaotic systems. We prove that after some short time a Gaussian wavepacket becomes a primitive WKB state. From then on, the state can be propagated using the standard TDWKB scheme. Complex trajectories are not necessary to account for the long-time propagation. The Wigner function of the evolving state develops the structure of a classical filament plus quantum oscillations, with phase and amplitude being determined by geometric properties of a classical manifold.

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Raphael N. P. Maia, Fernando Nicacio, Raul O. Vallejos, Fabricio Toscano. 2008-02-12. WKB Propagation of Gaussian Wavepackets. https://doi.org/10.1103/physrevlett.100.184102

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