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Propagation of Wigner functions for the Schroedinger equation with a perturbed periodic potential

Stefan Teufel·Gianluca Panati
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Abstract

Let $V_\Gamma$ be a lattice periodic potential and $A$ and $\phi$ external electromagnetic potentials which vary slowly on the scale set by the lattice spacing. It is shown that the Wigner function of a solution of the Schroedinger equation with Hamiltonian operator $H = {1/2} (-\I\nabla_x - A(\epsilon x))^2 + V_\Gamma (x) + \phi(\epsilon x)$ propagates along the flow of the semiclassical model of solid states physics up an error of order $\epsilon$. If $\epsilon$-dependent corrections to the flow are taken into account, the error is improved to order $\epsilon^2$. We also discuss the propagation of the Wigner measure. The results are obtained as corollaries of an Egorov type theorem proved in a previous paper (math-ph/0212041).

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Stefan Teufel, Gianluca Panati. 2004-03-19. Propagation of Wigner functions for the Schroedinger equation with a perturbed periodic potential. https://arxiv.org/abs/math-ph/0403037

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