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Editors' Suggestion in PRB

20.09.2018

Our paper "Transverse vortex commensurability effect and sign change of the Hall voltage in superconducting YBa2Cu3O7−δ thin films with a nanoscale periodic pinning landscape" got selected by the editors.

In superconductors with a periodic pinning potential, the vortices can lock into a commensurate arrangement, where each pin is filled by one vortex. Then, an intriguing duality between conduction electrons in a normal metal and mobile vortices in a superconductor arises. While the mutual repulsion of electrons can evoke a Mott insulator, the interaction between mobile and commensurably trapped vortices can lead to a vortex Mott metal-to-insulator transition with vanishing resistance. The authors report on a hitherto unknown manifestation of such a state, uncovered by measurements of the voltage orthogonal to the injected current. This vortex Hall effect exhibits a sharp peak and a change of sign when the number of vortices exactly matches that of the pins.

https://doi.org/10.1103/PhysRevB.98.104508

Contour plot of the Hall coefficient at various temperatures and magnetic fields of a YBCO film with a columnar defect array. The bright area corresponds to a maximum of the Hall effect at the matching field. The dotted line indicates the bifurcation, where the Hall effect emerges with different sign.