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arXiv · 2507.04876

Algebraic Criterion and Graph-Theoretic Construction of Intrinsic Superconducting Diode Effects

Ran Wang·Ning Hao
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Abstract

The intrinsic superconducting diode effect (SDE) is distinguished from the Josephson diode effect (JDE) by its manifestation of nonreciprocal critical current phenomena within a monolithic superconductor, typically linked to finite-momentum Cooper pairing. The long-standing assumption that SDE requires co-breaking of time-reversal and inversion symmetries proves to be necessary but not sufficient. In this work, we propose a universal diagnostic criterion for intrinsic SDE, expressed as two inequalities evaluated directly from the bare Hamiltonian. This criterion further reveals a graph-theoretic construction for nonreciprocal models, offering design principles that extend beyond superconductivity.

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Ran Wang, Ning Hao. 2025-07-07. Algebraic Criterion and Graph-Theoretic Construction of Intrinsic Superconducting Diode Effects. https://doi.org/10.1103/nj28-lj7k

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