Dresden 2006 – wissenschaftliches Programm

Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe

SYIM: Intrinsic Modes

SYIM 1: Intrinsic Modes I

SYIM 1.3: Hauptvortrag

Donnerstag, 30. März 2006, 15:30–16:00, HSZ 04

Generating and shepherding intrinsic localized modes in macroscopic and microscopic lattices — •Albert J. Sievers — Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, NY 14853-2501, USA

It had been known for some time that nonlinearity and discreteness play important roles in many branches of condensed matter physics as evidenced by the appearance of domain walls, kinks and solitons. A recent discovery is that localized dynamical energy in a perfect nonlinear lattice can be stabilized by the lattice discreteness. Intrinsic localized modes (ILMs) are the resulting feature. Their energy profiles resemble those of localized modes at defects in a harmonic lattice but, like solitons, they can propagate; however, in contrast with solitons, collisions between such excitations result in energy transfer between them with the more localized excitations stealing energy from the less localized ones. Our recent experimental studies involve near steady state locking of ILMs. We demonstrate both the manipulation of localized energy along micromechanical arrays [1] and also the generation of countable ILMs [2] and their controlled switching [3] in an atomic lattice. Such steady-state ILM locking techniques should be useful for producing other kinds of dynamical energy localization.
This work is supported by NSF-DMR. Work in collaboration with L. English, B. Hubbard, M. Sato, U. Schwarz and J. Wrubel.
[1] M. Sato, B. E. Hubbard, A. J. Sievers, Rev. Mod. Phys., in press (2005).
[2] M. Sato & A. J. Sievers, Nature 432, 486 (2004).
[3] J. Wrubel, M. Sato, A. J. Sievers, Phys. Rev. Lett., accepted (2005).