Observation of band renormalization effects in hole-doped high-Tc Superconductors.
We report a systematic high-resolution angle-resolved photoemission spectroscopy on high-T(c) superconductors Bi(2)Sr(2)Ca(n-1)Cu(n)O(2n+4) (n=1-3) to study the origin of many-body interactions responsible for superconductivity. For n=2 and 3, a sudden change in the energy dispersion, so called "kink", becomes pronounced on approaching (pi,0) in the superconducting state, while a kink appears only around the nodal direction in the normal state. For n=1, the kink shows no significant temperature dependence even across T(c). This could suggest that the coupling of electrons with Q=(pi,pi) magnetic mode is dominant in the superconducting state for multilayered cuprates, while the interactions at the normal state and that of single-layered cuprates have a different origin.
Sato
T
T
Department of Physics, Tohoku University, Sendai 980-8578, Japan.
Matsui
H
H
Takahashi
T
T
Ding
H
H
Yang
H-B
HB
Wang
S-C
SC
Fujii
T
T
Watanabe
T
T
Matsuda
A
A
Terashima
T
T
Kadowaki
K
K