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  • Letter
  • Open Access

Intrinsic nonmagnetic ϕ0 Josephson junctions in twisted bilayer graphene

M. Alvarado, P. Burset, and A. Levy Yeyati

  • Departamento de Física Teórica de la Materia Condensada, Condensed Matter Physics Center (IFIMAC) and Instituto Nicolás Cabrera, Universidad Autónoma de Madrid, 28049 Madrid, Spain

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Phys. Rev. Research 5, L032033 – Published 11 September, 2023

DOI: https://doi.org/10.1103/PhysRevResearch.5.L032033

Abstract

Recent experiments have demonstrated the possibility to design highly controllable junctions on magic angle twisted bilayer graphene, enabling the test of its superconducting transport properties. We show that the presence of chiral pairing in such devices manifests in the appearance of an anomalous Josephson effect (ϕ0 behavior) even in the case of symmetric junctions and without requiring any magnetic materials or fields. Such behavior arises from a combination of chiral pairing and nontrivial topology of the twisted bilayer graphene band structure that can effectively break inversion symmetry. Moreover, we show that the ϕ0 effect could be experimentally enhanced and controlled by electrostatic tuning of the junction transmission properties.

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Outline

Information

Phys. Rev. Research 5, L032033– Published 11 September, 2023
  • Received 13 March 2023
  • Revised 31 July 2023
  • Accepted 2 August 2023
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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