Signature of superfluid density in the single-particle excitation spectrum of Bi(2)Sr(2)CaCu(2)O(8+delta)
We report that the doping and temperature dependence of photoemission spectra near the Brillouin zone boundary of Bi(2)Sr(2)CaCu(2)O(8+delta)exhibit unexpected sensitivity to the superfluid density. In the superconducting state, the photoemission peak intensity as a function of doping scales with the superfluid density and the condensation energy. As a function of temperature, the peak intensity shows an abrupt behavior near the superconducting phase transition temperature where phase coherence sets in, rather than near the temperature where the gap opens. This anomalous manifestation of collective effects in single-particle spectroscopy raises important questions concerning the mechanism of high-temperature superconductivity.
Feng
DL
Department of Physics, Applied Physics, and Stanford Synchrotron Radiation Laboratory, Stanford University, Stanford, CA 94305, USA. Institute of Applied Physics, University of Tsukuba, Tsukuba, Ibaraki 305, Japan. Department of Applied Chem.
Lu
DH
Shen
KM
Kim
C
Eisaki
H
Damascelli
A
Yoshizaki
R
Shimoyama
J
Kishio
K
Gu
GD
Oh
S
Andrus
A
O'Donnell
J
Eckstein
JN
Shen
Z