BSCCO superconductors : hole-like fermi surface and doping dependence of the gap function.

Conference · Wed Aug 18 04:00:00 EDT 1999

OSTI ID:11940

Campuzano, J C; Ding, H; Fretwell, H M; Kadowaki, K; Kaminski, A; Mesot, J; Mochiku, T; Norman, M R; Paramekanti, A; Randeria, M; Sato, T; Takahashi, T; Takeuchi, T; Yokoya, T

We use the gradient of the energy-integrated angle resolved photoemission (ARPES) intensity in order to define precisely the Fermi surface (FS) in BSCCO superconductors. We show that, independent of the photon energy, the FS is a hole barrel centered at ({pi},{pi}), Then, the superconducting gap along the FS is precisely determined from ARPES measurements on over-doped and underdoped samples of Bi2212. As the doping decreases, the maximum gap increases, but the slope of the gap near the nodes decreases. Though consistent with d-wave symmetry, the gap with underdoping cannot be fit by the simple cos(k{sub x})-cos(k{sub y}) form. A comparison of our ARPES results with available penetration depth data indicates that the renormalization of the linear T suppression of the superfluid density at low temperatures due to quasiparticle excitations around the d-wave nodes is large and doping dependent.

• Research Organization: Argonne National Lab., IL (US)
• Sponsoring Organization: US Department of Energy (US)
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 11940
• Report Number(s): ANL/MSD/CP-99834
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BISMUTH OXIDES
CALCIUM OXIDES
COPPER OXIDES
ENERGY GAP
FERMI LEVEL
HIGH-TC SUPERCONDUCTORS
PENETRATION DEPTH
PHOTOEMISSION
STRONTIUM OXIDES