paper

Identification of a New Form of Electron Coupling in Bi2Sr2CaCu2O8 Superconductor by Laser-Based Angle-Resolved Photoemission

arXiv:0711.1706 · doi:10.1103/PhysRevLett.100.107002

Abstract

Laser-based angle-resolved photoemission measurements with super-high resolution have been carried out on an optimally-doped Bi $_{2}$ Sr $_{2}$ CaCu $_{2}$ O $_{8}$ high temperature superconductor. New high energy features at $\sim$ 115 meV and $\sim$ 150 meV, besides the prominent $\sim$ 70 meV one, are found to develop in the nodal electron self-energy in the superconducting state. These high energy features, which can not be attributed to electron coupling with single phonon or magnetic resonance mode, point to the existence of a new form of electron coupling in high temperature superconductors.

4 pages, 4 figures