%0 Journal Article %1 noauthororeditor %A Vigliotti, Lucia %A Calzona, Alessio %A Trauzettel, Björn %A Sassetti, Maura %A Traverso Ziani, Niccolò %D 2022 %J New J. Phys. %K a %P 053017 %R 10.1088/1367-2630/ac643b %T Anomalous flux periodicity in proximitised quantum spin Hall constrictions %U https://iopscience.iop.org/article/10.1088/1367-2630/ac643b %V 24 %X We theoretically analyse a long constriction between the helical edge states of a two-dimensional topological insulator. The constriction is laterally tunnel-coupled to two superconductors and a magnetic field is applied perpendicularly to the plane of the two-dimensional topological insulator. The Josephson current is calculated analytically up to second order in the tunnel coupling both in the absence and in the presence of a bias (DC and AC Josephson currents). We show that in both cases the current acquires an anomalous 4π-periodicity with respect to the magnetic flux that is absent if the two edges are not tunnel-coupled to each other. The result, that provides at the same time a characterisation of the device and a possible experimental signature of the coupling between the edges, is stable against temperature. The processes responsible for the anomalous 4π-periodicity are the ones where, within the constriction, one of the two electrons forming a Cooper pair tunnels between the two edges.

@article{noauthororeditor, abstract = {We theoretically analyse a long constriction between the helical edge states of a two-dimensional topological insulator. The constriction is laterally tunnel-coupled to two superconductors and a magnetic field is applied perpendicularly to the plane of the two-dimensional topological insulator. The Josephson current is calculated analytically up to second order in the tunnel coupling both in the absence and in the presence of a bias (DC and AC Josephson currents). We show that in both cases the current acquires an anomalous 4π-periodicity with respect to the magnetic flux that is absent if the two edges are not tunnel-coupled to each other. The result, that provides at the same time a characterisation of the device and a possible experimental signature of the coupling between the edges, is stable against temperature. The processes responsible for the anomalous 4π-periodicity are the ones where, within the constriction, one of the two electrons forming a Cooper pair tunnels between the two edges.}, added-at = {2023-10-06T15:20:51.000+0200}, author = {Vigliotti, Lucia and Calzona, Alessio and Trauzettel, Björn and Sassetti, Maura and Traverso Ziani, Niccolò}, biburl = {https://www.bibsonomy.org/bibtex/2c07392a2127ada8a839077d43b520335/ctqmat}, day = 11, description = {Anomalous flux periodicity in proximitised quantum spin Hall constrictions - IOPscience}, doi = {10.1088/1367-2630/ac643b}, interhash = {02f0f3771a889b7ed96b8236178911af}, intrahash = {c07392a2127ada8a839077d43b520335}, journal = {New J. Phys.}, keywords = {a}, month = {05}, pages = 053017, timestamp = {2023-10-06T15:20:51.000+0200}, title = {Anomalous flux periodicity in proximitised quantum spin Hall constrictions}, url = {https://iopscience.iop.org/article/10.1088/1367-2630/ac643b}, volume = 24, year = 2022 }