Regensburg 2010 – wissenschaftliches Programm
TT 24.2: Vortrag
Mittwoch, 24. März 2010, 14:15–14:30, H19
Superconducting Coherence Peak in the Electronic Excitations of a Single-Layer Bi2201 Cuprate Superconductor — •Jia Wei1,2, Martin Aeschlimann1, and Donglai Feng2 — 1Department of Physics, University of Kaiserslautern, Fachbereich Physik, Erwin Schoodinger Str. 46, 67663 Kaiserslautern, Germany — 21Department of Physics, Surface Physics Laboratory (National Key Laboratory) and Advanced Materials Laboratory, Fudan University, Shanghai 200433, P. R. China
Angle resolved photoemission spectroscopy study is reported on a high quality optimally doped Bi(La)2201 high-Tc superconductor. In the antinodal region with a maximal d-wave gap, the symbolic superconducting coherence peak, forming a so-called "peak-dip-hump" (PDH) structure, which has been widely observed in multi-CuO2-layer cuprate superconductors, is unambiguously observed in a single-layer system. We have discovered the PDH in the antinodal region of the La-Bi2201. The 19 meV peak-dip separation seriously challenges models based on electron-phonon interactions. Meanwhile, this energy scale is much smaller than its counterparts in multi-layered compounds, but correlates with the energy scales of spin excitations in single layer cuprates. Our data provide a critical piece to the global picture of the bosonic mode and gap in cuprates, which would help to eventually resolve controversial issues and uncover the "glue" of high-Tc superconductivity.