Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Direct determination of the collective pinning radius in high
  temperature superconductors   We study finite-size effects at the onset of the irreversible magnetic
behaviour of micron-sized Bi$_2$Sr$_2$CaCu$_2$O$_{8+\delta}$ single crystals by
using silicon micro-oscillators. We find an irreversibility line appearing well
below the thermodynamic Bragg-glass melting line at a magnetic field which
increases both with increasing the sample radius and with decreasing the
temperature. We show that this size-dependent irreversibility line can be
identified with the crossover between the Larkin and the random manifold
regimes of the vortex lattice transverse roughness. Our method allows to
determine the three-dimensional weak collective pinning Larkin radius in a {\it
direct way}.

12
The categories of this paper are: nucl-th
9
The categories of this paper are: nlin
35
The categories of this paper are: mtrl-th
34
The categories of this paper are: chem-ph
17
The categories of this paper are: q-fin
19
The categories of this paper are: eess
24
The categories of this paper are: dg-ga
11
The categories of this paper are: hep-lat
33
The categories of this paper are: plasm-ph
27
The categories of this paper are: comp-gas
31
The categories of this paper are: ao-sci
36
The categories of this paper are: cmp-lg
30
The categories of this paper are: q-alg
1
The categories of this paper are: cs
10
The categories of this paper are: q-bio
20
The categories of this paper are: acc-phys