Abstract
Photoemission spectra of underdoped and lightly-doped (, ) (BSCCO) have been measured and compared with those of (LSCO). The lower-Hubbard band of the insulating BSCCO, like , shows a stronger dispersion than from to . The flat band at is found generally deeper in BSCCO. These observations together with the Fermi-surface shapes and the chemical potential shifts indicate that the next-nearest-neighbor hopping of the single-band model is larger in BSCCO than in LSCO and that rather than the super-exchange influences the pseudogap energy scale.
- Received 14 April 2004
DOI:https://doi.org/10.1103/PhysRevB.70.092503
©2004 American Physical Society