← Back to search

Delocalized Quasiparticles in the Vortex State of an Overdoped High- Tc Superconductor Probed by C63u NMR

G.-q. Zheng, H. Ozaki, Y. Kitaoka, P. Kuhns, A. P. Reyes, W. G. Moulton

DOI 10.1103/PhysRevLett.88.077003 · Physical Review Letters

T1

Active bibliographic source — not scientific approval

Bibliographic access preserves source history; it does not approve extracted materials or validate reported claims. Review warnings on each occurrence separately.

Abstract

We report the spin Knight shift ( Ks) and the nuclear spin-lattice relaxation rate ( 1/T1) in the vortex state as a function of magnetic field ( H) up to 28 T in the high- Tc superconductor TlSr2CaCu2O6.8 ( Tc=68K). At low temperatures well below Tc, both Ks and 1/T1 measured around the middle point between the two nearest vortices (saddle point) increase substantially with increasing field, which indicate that the quasiparticle states with an ungapped spectrum are extended outside the vortex cores in a d-wave superconductor. The density of states (DOS) around the saddle point is found to be ∼κN0H/Hc2, with κ=0.5–0.7 and N0 being the normal-state DOS.

Source-reported materials — not catalogue approval

FormulaReported Tc (K)Pressure (GPa)Type
TlSr2CaCu2O6.8

Archive — visibility unverified

Source-occurrence policy only; no material identity or catalogue acceptance is inferred from the formula.

68Pressure not reportedunknown

Similar papers