Year: 2026
Type: article
Abstract: The pursuit of dissipationless spin supercurrents is a central theme in superconducting spintronics. We propose a field-free Josephson junction using an inhomogeneous altermagnetic interlayer with in-plane Néel vectors. We show that the current-phase relation and the critical Josephson current are highly sensitive to the misorientation angle between the altermagnetic layers' Néel vectors. Specifically, at a $π$ misorientation with equal layer thicknesses the spatial oscillations of the superconducting pair amplitude, governed by the center-of-mass momentum, undergo mutual cancellation. This compensation suppresses individual layer pair-breaking, significantly enhancing the critical current and eliminating $0$-$π$ transitions. Furthermore, the non-collinear alignment of the Néel vectors facilitates the emergence of a net spin-polarized Josephson current. This spin current serves as a distinct signature of spin-triplet pair correlations, generated by the spin-dependent momentum shifts inherent to the altermagnetic exchange field. Our results establish a highly tunable, field-free platform for the realization of dissipationless spintronic devices.
DOI: 10.1103/wzx9-58gr
Language: English
Subfield: Condensed Matter Physics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Awards: Anyon in superconducting junctions: Beyond Majorana fermion, G2109078276, G225243530, Higher-order relativistic corrections to strongly correlated electron systems, Superconductivity with unconventional Magnetism: Theoretical Challenges for Next-Generation Quantum Devices, Phase sensitive detection and non-local measurements of time-reversal symmetry broken superconductors, Non-Hermitian topology for novel superconducting states, G5283148391, G664330551, Theory of exotic superconductivity in Majorana fermion-electron coupled system, G7870925207, スピン三重項トポロジカル超伝導体におけるマヨラナ粒子状態の検出, Anyons at superconducting junctions involving quasiparticle excitations with fractional charges
OpenAlex ID: W7160306922