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Wavepacket reconstruction via local dynamics in a parabolic lattice

Quentin Thommen·Veronique Zehnle·Jean Claude Garreau
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Abstract

We study the dynamics of a wavepacket in a potential formed by the sum of a periodic lattice and of a parabolic potential. The dynamics of the wavepacket is essentially a superposition of ``local Bloch oscillations'', whose frequency is proportional to the local slope of the parabolic potential. We show that the amplitude and the phase of the Fourier transform of a signal characterizing this dynamics contains information about the amplitude and the phase of the wavepacket at a given lattice site. Hence, {\em complete} reconstruction of the the wavepacket in the real space can be performed from the study of the dynamics of the system.

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Quentin Thommen, Veronique Zehnle, Jean Claude Garreau. 2002-03-06. Wavepacket reconstruction via local dynamics in a parabolic lattice. https://doi.org/10.1103/physreva.67.013416

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