Tobias Ambjörnsson
Senior lecturer
Severe slowing-down and universality of the dynamics in disordered interacting many-body systems: ageing and ultraslow diffusion
Author
Summary, in English
Low-dimensional, many-body systems are often characterized by ultraslow dynamics. We study a labelled particle in a generic system of identical particles with hard-core interactions in a strongly disordered environment. The disorder is manifested through intermittent motion with scale-free sticking times at the single particle level. While for a non-interacting particle we find anomalous diffusion of the power-law form < x(2)(t)> similar or equal to t(alpha) of the mean squared displacement with 0 < alpha < 1, we demonstrate here that the combination of the disordered environment with the many-body interactions leads to an ultraslow, logarithmic dynamics < x(2)(t)> similar or equal to log(1/2)t with a universal 1/2 exponent. Even when a characteristic sticking time exists but the fluctuations of sticking times diverge we observe the mean squared displacement < x(2)(t)> similar or equal to t(gamma) with 0 < gamma < 1/2, that is slower than the famed Harris law < x(2)(t)> similar or equal to t(1/2) without disorder. We rationalize the results in terms of a subordination to a counting process, in which each transition is dominated by the forward waiting time of an ageing continuous time process.
Department/s
- Computational Biology and Biological Physics - Has been reorganised
Publishing year
2014
Language
English
Publication/Series
New Journal of Physics
Volume
16
Document type
Journal article
Publisher
IOP Publishing
Topic
- Biophysics
- Other Physics Topics
Keywords
- single-file diffusion
- continuous time random walks
- ageing
Status
Published
ISBN/ISSN/Other
- ISSN: 1367-2630