Changes in superconducting gap anisotropy with doping and implications for the penetration depth.

Conference · Mon Dec 20 04:00:00 EST 1999 · Int. J. Mod. Phys. B

DOI:https://doi.org/10.1142/S0217979299003726· OSTI ID:917644

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

The momentum dependence of the superconducting gap at low temperatures is precisely determined from angle resolved photoemission (ARPES) measurements on overdoped 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. We suggest that this arises due to the increasing importance of long range interactions as one approaches the insulator. Furthermore, a comparison of our ARPES results with available penetration depth data clearly 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 Laboratory (ANL)
• Sponsoring Organization: SC; NSF; FOR
• DOE Contract Number: AC02-06CH11357
• OSTI ID: 917644
• Report Number(s): ANL/MSD/CP-99833
• Conference Information: Journal Name: Int. J. Mod. Phys. B Journal Issue: 29-31 ; Dec. 20, 1999 Journal Volume: 13
• Country of Publication: United States
• Language: ENGLISH

Related Subjects

36 MATERIALS SCIENCE
ANISOTROPY
BISMUTH OXIDES
CALCIUM OXIDES
COPPER OXIDES
DOPED MATERIALS
ENERGY GAP
INTERACTION RANGE
PENETRATION DEPTH
PHOTOEMISSION
RENORMALIZATION
STRONTIUM OXIDES
SUPERCONDUCTORS