Electronic properties of layered oxides: Pulsed laser deposition of YBCO films for in-situ studies by photoemission spectroscopy

Due to imperfect surfaces of most cuprate samples, almost all photoemission studies in the past decade were performed on Bi2Sr2CaCu2O8+x, even though a large fraction of other studies and electronic applications was reported for YBa2Cu3O7-delta (YBCO) family of superconducting compounds. In order to systematically study the gap parameter and the Fermi surface variation in high symmetry directions of YBCO and related oxide films we have constructed a new facility at the Wisconsin Synchrotron Radiation Center. We use the pulsed laser ablation (PLD) system that is directly linked to the photoemission chamber. In our unique approach, the samples never leave the controlled ambient and we oxidize our films, either by molecular oxygen or by ozone. Tn this paper, we summarize some of the most relevant recent results on electronic properties of layered oxides and describe our new facility for the study of YBCO and related oxide films.