Probing the order parameter symmetry of two-dimensional superconductors by twisted Josephson interferometry

Abstract

Probing the superconducting order parameter symmetry is a crucial step towards understanding the pairing mechanism in unconventional superconductors. Inspired by the recent discoveries of superconductivity in various van der Waals materials, and the availability of the relative twist angle as a continuous tuning knob in these systems, we propose a general setup for probing the order parameter symmetry of two-dimensional superconductors in twisted Josephson junctions. The junction is composed of an anisotropic s-wave superconductor as a probe and another superconductor with an unknown order parameter symmetry. Assuming momentum-resolved tunneling, we investigate signatures of different order parameter symmetries in the twist angle dependence of the critical current, the current-phase relations, and magnetic field dependence. As a concrete example, we study a twisted Josephson junction between NbSe2 and magic angle twisted bilayer graphene.

15 pages, 5 figures

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Cited by in corpus (5)

• Josephson diode effects in twisted nodal superconductors
• Theory of phonon spectroscopy with the quantum twisting microscope
• Momentum-resolved spectroscopy of superconductivity with the quantum twisting microscope
• Tuning monolayer superconductivity in twisted NbSe${}_2$ graphene heterostructures
• Twisted Nodal Superconductors