Current-phase relation of a short multi-mode Bi2Se3 topological insulator nanoribbon Josephson junction with ballistic transport modes

Funding Information: This work was supported by the European Union’s H2020 under the Marie Curie Actions (No. 766025-QuESTech). This work has been supported by the European Union’s Horizon 2020 Research and Innovation Program (Grant Agreement No. 766714/HiTIMe). K Niherysh acknowledges the financial support of the ‘Strengthening of the capacity of doctoral studies at the University of Latvia within the framework of the new doctoral model’, identification no. 8.2.2.0/20/I/006. | openaire: EC/H2020/766025/EU//QuESTech | openaire: EC/H2020/766714/EU//HiTIMeWe used the asymmetric superconducting quantum interference device (SQUID) technique to extract the current phase relation (CPR) of a Josephson junction with a 3D-topological insulator (3D-TI) Bi2Se3 nanobelt as the barrier. The obtained CPR shows deviations from the standard sinusoidal CPR with a pronounced forward skewness. At temperatures below 200 mK, the junction skewness values are above the zero temperature limit for short diffusive junctions. Fitting of the extracted CPR shows that most of the supercurrent is carried by ballistic topological surface states (TSSs), with a small contribution of diffusive channels primarily due to the bulk. These findings are instrumental in engineering devices that can fully exploit the properties of the topologically protected surface states of 3D TIs.Peer reviewe