Physics – Condensed Matter – Statistical Mechanics
Scientific paper
2008-05-30
Physics
Condensed Matter
Statistical Mechanics
4 pages, 3 figures
Scientific paper
10.1103/PhysRevLett.102.024101
In the absence of nonlinearity all eigenmodes of a chain with disorder are spatially localized (Anderson localization). The width of the eigenvalue spectrum, and the average eigenvalue spacing inside the localization volume, set two frequency scales. An initially localized wavepacket spreads in the presence of nonlinearity. Nonlinearity introduces frequency shifts, which define three different evolution outcomes: i) localization as a transient, with subsequent subdiffusion; ii) the absence of the transient, and immediate subdiffusion; iii) selftrapping of a part of the packet, and subdiffusion of the remainder. The subdiffusive spreading is due to a finite number of packet modes being resonant. This number does not change on average, and depends only on the disorder strength. Spreading is due to corresponding weak chaos inside the packet, which slowly heats the cold exterior. The second moment of the packet is increasing as $t^{\alpha}$. We find $\alpha=1/3$.
Flach Sergej
Krimer D.
Skokos Ch
No associations
LandOfFree
Universal spreading of wavepackets in disordered nonlinear systems does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Universal spreading of wavepackets in disordered nonlinear systems, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Universal spreading of wavepackets in disordered nonlinear systems will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-317468