Gap anisotropy and van Hove singularities in high {Tc} superconductors
- ESPCI, Paris (France). Lab. de Physique du Solide
The authors compute the superconducting gap {Delta}{sub {rvec k}} using a simple band structure of the CuO{sub 2} planes in the high Tc materials. They suppose that for materials with doping corresponding to maximum {Tc}, the van Hove singularities lie close to the Fermi level as is confirmed by many photoemission experiments. They use a electron-photon interaction with weak screening, they find a strong gap anisotropy. For Bi 2212, {Delta} is maximum along the 100 and 010 directions with values between 20 and 30 meV and minimum along 110 with values between 0 and 10 meV. They use this anisotropic gap to compute the quasi-particle excitations density of states and the tunneling current-voltage I(V) characteristic for N-I-S and S-I-S junctions. This model agrees remarkably well with recent experiments of tunneling spectroscopy in high {Tc} cuprates.
- OSTI ID:
- 538197
- Report Number(s):
- CONF-960163--; ISBN 0-8194-2070-0
- Country of Publication:
- United States
- Language:
- English
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