Download file (2.3 MB)
Download as zip (2.03 MB)

Collection

Citation

Description:

Magic-angle twisted bilayer graphene (MATBG) combines in one single material different phases like insulating, metallic and superconducting. These phases and their in-situ tunability make MATBG an important platform for the fabrication of superconducting devices. We realize a split gate-defined geometry which enables us to tune the width of a superconducting channel formed in MATBG. We observe a smooth transition from superconductivity to highly resistive transport by progressively reducing the channel width using the split gates or by reducing the density in the channel. Using the gate-defined constriction, we control the flow of the supercurrent, either guiding it through the constriction or throughout the whole device or even blocking its passage completely. This serves as a foundation for developing quantum constriction devices like superconducting quan- tum point contacts, quantum dots, and Cooper-pair boxes in MATBG.

Rights:

• Creative Commons BY Attribution 4.0 International
  

Keyword: Magic-angle, superconducting devices, split-gate

Date published: 2024-03-06

Publisher: American Physical Society (APS)

Journal:

• Physical Review Research (ISSN: 26431564) vol. 6 issue. 1 L012051

Funding:

• European Research Council 951541
• Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung 51NF40-185902
• Japan Society for the Promotion of Science 21H05233
• Japan Society for the Promotion of Science 23H02052
• Ministry of Education, Culture, Sports, Science and Technology

Manuscript type: Publisher's version (Version of record)

MDR DOI:

First published URL: https://doi.org/10.1103/physrevresearch.6.l012051

Related item:

Other identifier(s):

Contact agent:

Updated at: 2025-02-23 22:47:15 +0900

Published on MDR: 2025-02-23 22:47:15 +0900