Algebraic criterion and graph-theoretic construction of intrinsic superconducting diode effects
Phys. Rev. B 114, 084504 – Published 7 August, 2026
DOI: https://doi.org/10.1103/nj28-lj7k
Abstract
The intrinsic superconducting diode effect (SDE) is distinguished from the Josephson diode effect 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 cobreaking of time-reversal and inversion symmetries proves to be necessary but not sufficient. In this work, we propose an algebraic 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.
