- Letter
Andreev processes in mesoscopic multiterminal graphene Josephson junctions
Phys. Rev. B 107, L140503 – Published 12 April, 2023
DOI: https://doi.org/10.1103/PhysRevB.107.L140503
Abstract
There is growing interest in using multiterminal Josephson junctions (MTJJs) as a platform to artificially emulate topological phases and to investigate superconducting mechanisms such as multiplet Cooper pairings. Current experimental signatures in MTJJs have led to conflicting interpretations of the salient features. In this work, we report a collaborative experimental and theoretical investigation of graphene-based four-terminal Josephson junctions. We observe resonant features in the differential resistance maps that resemble those ascribed to multiplet Cooper pairings. To understand these features, we model our junctions using a circuit network of resistively and capacitively shunted junctions (RCSJs). We find that the RCSJ model successfully reproduces the observed multiplet features. Therefore, our study suggests that differential resistance measurements alone are insufficient to conclusively distinguish resonant Andreev reflection processes from semiclassical circuit-network effects.