Authors: G. Zechner and W. Lang
Physical Review B 98, 104508 (2018)
The transverse (Hall) voltage in thin ﬁlms of the high-temperature superconductor YBa2Cu3O7−δ with an artiﬁcial periodic pinning array is investigated. Columnar defect regions along the crystallographic c axis, in which superconductivity is suppressed, are created by irradiation with He+ ions through a silicon stencil mask. The commensurate arrangement of magnetic ﬂux quanta with the artiﬁcial defect lattice is conﬁrmed by maxima of the critical current and minima of the resistance, respectively. The magnetic ﬁeld dependence of the transverse voltage reveals a commensurability effect characterized by a narrow peak of the Hall coefﬁcient with reversed polarity compared to the background signal. This signature of vortex matching disappears at larger vortex velocities substantiating its close connection with enhanced pinning of vortices at the periodic pinning landscape.