title: Circular dichroism in angle-resolved photoemission spectra of under- and overdoped Pb-Bi2212.
abstract: We use angle-resolved photoemission with circularly polarized excitation to demonstrate that in the 5 x 1 superstructure-free (Pb,Bi)(2)Sr(2)CaCu(2)O(8+delta) (Pb-Bi2212) material there are no signatures of time-reversal symmetry breaking in the sense of the criteria developed earlier [Nature (London) 416, 610 (2002)]]. The dichroic signal retains reflection antisymmetry as a function of temperature and doping and in all mirror planes, precisely defined by the experimental dispersion at low energies. The obtained results demonstrate that the signatures of time-reversal symmetry violation in pristine Bi2212, as determined by angle-resolved photoemission spectroscopy, are not a universal feature of all cuprate superconductors.
authors.affiliation: Institute for Solid State Research, IFW-Dresden, PO Box 270116, D-01171 Dresden, Germany.
authors.forename: S V
authors.initials: SV
authors.lastname: Borisenko
authors.forename: A A
authors.initials: AA
authors.lastname: Kordyuk
authors.forename: A
authors.initials: A
authors.lastname: Koitzsch
authors.forename: T K
authors.initials: TK
authors.lastname: Kim
authors.forename: K A
authors.initials: KA
authors.lastname: Nenkov
authors.forename: M
authors.initials: M
authors.lastname: Knupfer
authors.forename: J
authors.initials: J
authors.lastname: Fink
authors.forename: C
authors.initials: C
authors.lastname: Grazioli
authors.forename: S
authors.initials: S
authors.lastname: Turchini
authors.forename: H
authors.initials: H
authors.lastname: Berger