Dynamical upper bounds on wavepacket spreading

Published

Journal Article

We derive a general upper bound on the spreading rate of wavepackets in the framework of Sohrödinger time evolution. Our result consists of showing that a portion of the wavepacket cannot escape outside a ball whose size grows dynamically in time, where the rate of this growth is determined by properties of the spectral measure and by spatial properties of solutions of an associated time-independent Schrödinger equation. We also derive a new lower bound on the spreading rate, which is strongly connected with our upper bound. We apply these new bounds to the Fibonacci Hamiltonian - the most studied one-dimensional model of quasicrystals. As a result, we obtain for this model upper and lower dynamical bounds establishing wavepacket spreading rates which are intermediate between ballistic transport and localization. The bounds have the same qualitative behavior in the limit of large coupling.

Duke Authors

Cited Authors

  • Killip, R; Kiselev, A; Last, Y

Published Date

  • October 1, 2003

Published In

Volume / Issue

  • 125 / 5

Start / End Page

  • 1165 - 1198

International Standard Serial Number (ISSN)

  • 0002-9327

Citation Source

  • Scopus