Topological insulator nanoribbon Josephson junctions: Evidence for size effects in transport properties
Artikel i vetenskaplig tidskrift, 2020
We have used Bi 2 Se 3 nanoribbons, grown by catalyst-free physical vapor deposition to fabricate high quality Josephson junctions with Al superconducting electrodes. In our devices, we observe a pronounced reduction of the Josephson critical current density J c by reducing the width of the junction, which in our case corresponds to the width of the nanoribbon. Because the topological surface states extend over the entire circumference of the nanoribbon, the superconducting transport associated with them is carried by modes on both the top and bottom surfaces of the nanoribbon. We show that the J c reduction as a function of the nanoribbon width can be accounted for by assuming that only the modes traveling on the top surface contribute to the Josephson transport as we derive by geometrical consideration. This finding is of great relevance for topological quantum circuitry schemes since it indicates that the Josephson current is mainly carried by the topological surface states.
Författare
Gunta Kunakova
Chalmers, Mikroteknologi och nanovetenskap, Kvantkomponentfysik
Latvijas Universitate
Ananthu Pullukattuthara Surendran
Chalmers, Mikroteknologi och nanovetenskap, Kvantkomponentfysik
Domenico Montemurro
Universita degli Studi di Napoli Federico II
Chalmers, Mikroteknologi och nanovetenskap, Kvantkomponentfysik
Matteo Salvato
Universita degli Studi di Roma Tor Vergata
Dmitry Golubev
Aalto-Yliopisto
J. Andzane
Latvijas Universitate
Donats Érts
Latvijas Universitate
Thilo Bauch
Chalmers, Mikroteknologi och nanovetenskap, Kvantkomponentfysik
Floriana Lombardi
Chalmers, Mikroteknologi och nanovetenskap, Kvantkomponentfysik
Journal of Applied Physics
0021-8979 (ISSN) 1089-7550 (eISSN)
Vol. 128 19 194304Ämneskategorier
Annan fysik
Fusion, plasma och rymdfysik
Den kondenserade materiens fysik
DOI
10.1063/5.0022126