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Fermi surface and quasiparticle excitations of overdoped Tl2Ba2CuO6 + delta
M Platé1, J D F Mottershead, I S Elfimov
1Department of Physics and Astronomy, University of British Columbia, Vancouver, Canada.
Abstract:
The high-T(c) superconductor Tl(2)Ba(2)CuO(6 + delta) is studied by angle-resolved photoemission spectroscopy. For a very overdoped T(c) = 30 K sample, the Fermi surface consists of a single large hole pocket centered at (pi, pi) and is approaching a topological transition. Although a superconducting gap with d(x(2)-y(2)) symmetry is tentatively identified, the quasiparticle evolution with momentum and binding energy exhibits a marked departure from the behavior observed in under and optimally doped cuprates. The relevance of these findings to scattering, many-body, and quantum-critical phenomena is discussed.
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