Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The onset of the vortex-like Nernst signal above Tc in La_{2-x}Sr_xCuO_4
  and Bi_2Sr_{2-y}La_yCuO_6   The diffusion of vortices down a thermal gradient produces a Josephson signal
which is detected as the vortex Nernst effect. In a recent report, Xu et al.,
Nature 406, 486 (2000), an enhanced Nernst signal identified with vortex-like
excitations was observed in a series of La_{2-x}Sr_xCuO_4 (LSCO) crystals at
temperatures 50-100 K above T_c. To pin down the onset temperature T_{\nu} of
the vortex-like signal in the lightly doped regime (0.03 < x < 0.07), we have
re-analyzed in detail the carrier contribution to the Nernst signal. By
supplementing new Nernst measurements with thermopower and Hall-angle data, we
isolate the off-diagonal Peltier conductivity \alpha_{xy} and show that its
profile provides an objective determination of T_{\nu}. With the new results,
we revise the phase diagram for the fluctuation regime in LSCO to accomodate
the lightly doped regime. In the cuprate Bi_2Sr_{2-y}La_yCuO_6, we find that
the carrier contribution is virtually negligible for y in the range 0.4-0.6.
The evidence for an extended temperature interval with vortex-like excitations
is even stronger in this system. Finally, we discuss how T_{\nu} relates to the
pseudogap temperature T* and the implications of strong fluctuations between
the pseudogap state and the d-wave superconducting state.

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The categories of this paper are: hep-lat
18
The categories of this paper are: econ
20
The categories of this paper are: acc-phys
33
The categories of this paper are: plasm-ph
9
The categories of this paper are: nlin
3
The categories of this paper are: physics
26
The categories of this paper are: bayes-an
23
The categories of this paper are: solv-int
34
The categories of this paper are: chem-ph
6
The categories of this paper are: astro-ph
0
The categories of this paper are: hep-ph
8
The categories of this paper are: hep-ex
2
The categories of this paper are: math
1
The categories of this paper are: cs
30
The categories of this paper are: q-alg
32
The categories of this paper are: atom-ph