English

Resetting of fluctuating interfaces at power-law times

Statistical Mechanics 2016-11-03 v1

Abstract

What happens when the time evolution of a fluctuating interface is interrupted with resetting to a given initial configuration after random time intervals τ\tau distributed as a power-law τ(1+α); α>0\sim \tau^{-(1+\alpha)};~\alpha > 0? For an interface of length LL in one dimension, and an initial flat configuration, we show that depending on α\alpha, the dynamics as LL \to \infty exhibits a rich long-time behavior. Without resetting, the interface width grows unbounded with time as tβt^\beta, where β\beta is the so-called growth exponent. We show that introducing resetting induces for α>1\alpha>1 and at long times fluctuations that are bounded in time. Corresponding to such a stationary state is a distribution of fluctuations that is strongly non-Gaussian, with tails decaying as a power-law. The distribution exhibits a cusp for small argument, implying that the stationary state is out of equilibrium. For α<1\alpha<1, resetting is unable to counter the otherwise unbounded growth of fluctuations in time, so that the distribution of fluctuations remains time dependent with an ever-increasing width even at long times. Although stationary for α>1\alpha>1, the width of the interface grows forever with time as a power-law for 1<α<α(w)1<\alpha < \alpha^{({\rm w})}, and converges to a finite constant only for larger α\alpha, thereby exhibiting a crossover at α(w)=1+2β\alpha^{({\rm w})}=1+2\beta. The time-dependent distribution of fluctuations for α<1\alpha<1 exhibits for small argument another interesting crossover behavior, from cusp to divergence, across α(d)=1β\alpha^{({\rm d})}=1-\beta. We demonstrate these results by exact analytical results for the paradigmatic Edwards-Wilkinson (EW) dynamical evolution of the interface, and further corroborate our findings by extensive numerical simulations of interface models in the EW and the Kardar-Parisi-Zhang universality class.

Keywords

Cite

@article{arxiv.1604.06627,
  title  = {Resetting of fluctuating interfaces at power-law times},
  author = {Shamik Gupta and Apoorva Nagar},
  journal= {arXiv preprint arXiv:1604.06627},
  year   = {2016}
}