The electronic structure of LaFeAsO, a parent compound of iron-arsenic superconductors, is studied by angle-resolved photoemission spectroscopy. By examining its dependence on photon energy, polarization, and sodium dosing, both the bulk and the surface contributions are identified. We find that a bulk band moves toward high binding energies below the structural transition temperature, and shifts smoothly across the spin-density-wave transition by about 25 meV. Our data suggest that the band reconstruction may play a crucial role in the spin-density-wave and the structural transitions. For the surface states, both the LaO-terminated and FeAs-terminated components are revealed. Certain small band shifts are observed for the FeAs-terminated surface states in the spin-density-wave state, which might be a reflection of the bulk electronic-structure reconstruction. Moreover, sharp quasiparticle peaks quickly rise at low temperatures, indicating drastic reduction in the scattering rate. A kink structure in one of the surface band is shown to be possibly related to the enhanced electron-phonon interactions on the polar surface.
Surface and bulk electronic structures of LaFeAsO studied by angle-resolved photoemission spectroscopy / L.X. Yang, B.P. Xie, Y. Zhang, C. He, Q.Q. Ge, X.F. Wang, X.H. Chen, M. Arita, J. Jiang, K. Shimada, M. Taniguchi, I. Vobornik, G. Rossi, J.P. Hu, D.H. Lu, Z.X. Shen, Z.Y. Lu, D.L. Feng. - In: PHYSICAL REVIEW. B, CONDENSED MATTER AND MATERIALS PHYSICS. - ISSN 1098-0121. - 82:10(2010), pp. 104519.1-104519.9.
|Titolo:||Surface and bulk electronic structures of LaFeAsO studied by angle-resolved photoemission spectroscopy|
|Parole Chiave:||Electronic, Optical and Magnetic Materials; Condensed Matter Physics|
|Settore Scientifico Disciplinare:||Settore FIS/03 - Fisica della Materia|
|Data di pubblicazione:||2010|
|Digital Object Identifier (DOI):||http://dx.doi.org/10.1103/PhysRevB.82.104519|
|Appare nelle tipologie:||01 - Articolo su periodico|