Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Scale-free channeling patterns near the onset of erosion of sheared
  granular beds   Erosion shapes our landscape and occurs when a sufficient shear stress is
exerted by a fluid on a sedimented layer. What controls erosion at a
microscopic level remains debated, especially near the threshold forcing where
it stops. Here we study experimentally the collective dynamics of the moving
particles, using a set-up where the system spontaneously evolves toward the
erosion onset. We find that the spatial organization of the erosion flux is
heterogeneous in space, and occurs along channels of local flux $\sigma$ whose
distribution displays scaling near threshold and follows $P(\sigma)\sim
J/\sigma$, where $J$ is the mean erosion flux. Channels are strongly correlated
in the direction of forcing but not in the transverse direction. We show that
these results quantitatively agree with a model where the dynamics is governed
by the competition of disorder (which channels mobile particles) and particle
interactions (which reduces channeling). These observations support that for
laminar flows, erosion is a dynamical phase transition which shares similarity
with the plastic depinning transition occurring in dirty superconductors. The
methodology we introduce here could be applied to probe these systems as well.

24
The categories of this paper are: dg-ga
16
The categories of this paper are: stat
21
The categories of this paper are: adap-org
29
The categories of this paper are: funct-an
34
The categories of this paper are: chem-ph
14
The categories of this paper are: math-ph
7
The categories of this paper are: hep-th
15
The categories of this paper are: nucl-ex
32
The categories of this paper are: atom-ph
8
The categories of this paper are: hep-ex
1
The categories of this paper are: cs
22
The categories of this paper are: chao-dyn
26
The categories of this paper are: bayes-an
10
The categories of this paper are: q-bio
0
The categories of this paper are: hep-ph
9
The categories of this paper are: nlin