Phys. Rev. B 78, 174522 (2008) [7 pages]Energy scales in the Raman spectrum of electron- and hole-doped cuprates within competing scenariosReceived 16 June 2008; revised 3 October 2008; published 21 November 2008 Recent experiments in underdoped hole-doped cuprates have shown the presence of two energy scales in the Raman spectrum in the superconducting state. This feature has a natural explanation in some models in which pseudogap and superconductivity compete. In electron-doped cuprates antiferromagnetic correlations are believed to survive in the superconducting state and are believed to produce a pseudogap above the critical temperature. Contrary to hole-doped systems, in electron-doped compounds only one energy scale appears since the pair-breaking Raman intensity peaks in both B1g (antinodal) and B2g (nodal) channels at a frequency of a few meV, typical of the superconducting order parameter. In this paper we analyze the different effects in the Raman spectrum of the competition between pseudogap and superconductivity in electron- and hole-doped cuprates. The difference in energy scales in both systems is explained in terms of the different truncation of the Fermi surface induced by the pseudogap. For electron-doped cuprates we also analyze the spectrum with antiferromagnetism and a nonmonotonic superconducting order parameter. © 2008 The American Physical Society URL:
http://link.aps.org/doi/10.1103/PhysRevB.78.174522
DOI:
10.1103/PhysRevB.78.174522
PACS:
74.72.−h, 71.10.−w, 78.20.Bh
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