Photoemission Evidence for a Remnant Fermi Surface and a d-Wave-Like Dispersion in Insulating Ca2CuO2Cl2
Abstract
An angle resolved photoemission study on Ca2CuO2Cl2, a parent compound of high Tc superconductors is reported. Analysis of the electron occupation probability, n(k) from the spectra shows a steep drop in spectral intensity across a contour that is close to the Fermi surface predicted by the band calculation. This analysis reveals a Fermi surface remnant even though Ca2CuO2Cl2 is a Mott insulator. The lowest energy peak exhibits a dispersion with approximately the |cos(kxa)-cos(kya)| form along this remnant Fermi surface. Together with the data from Dy doped Bi2Sr2CaCu2O(8 + delta) these results suggest that this d-wave like dispersion of the insulator is the underlying reason for the pseudo gap in the underdoped regime.
- Publication:
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Science
- Pub Date:
- December 1998
- DOI:
- 10.1126/science.282.5396.2067
- arXiv:
- arXiv:cond-mat/9903151
- Bibcode:
- 1998Sci...282.2067R
- Keywords:
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- Condensed Matter - Superconductivity
- E-Print:
- 9 pages, including 7 figures. Published in Science, one figure corrected