  Non-equilibrium studies of two-dimensional (2D) superconductors (SCs) with
Ising spin-orbit coupling are prerequisite for their successful application to
equilibrium spin-triplet Cooper pairs and, potentially, Majorana fermions. By
taking advantage of the recent discoveries of 2D SCs and their compatibility
with any other materials, we fabricate here non-local magnon devices to examine
how such 2D Ising superconductivity affects the conversion efficiency of magnon
spin to quasiparticle charge in superconducting flakes of 2H-NbSe2 transferred
onto ferrimagnetic insulating Y3Fe5O12. Comparison with a reference device
based on a conventionally paired superconductor shows that the Y3Fe5O12-induced
in-plane (IP) exchange spin-splitting in the NbSe2 flake is hindered by its
inherent out-of-plane (OOP) spin-orbit-field, which, in turn, limits the
transition-state enhancement of the spin-to-charge conversion efficiency. Our
out-of-equilibrium study highlights the significance of symmetry matching
between underlying Cooper pairs and exchange-induced spin-splitting for the
giant transition-state spin-to-charge conversion and may have implications
towards proximity-engineered spin-polarized triplet pairing via tuning the
relative strength of IP exchange and OOP spin-orbit fields in ferromagnetic
insulator/2D Ising SC bilayers.
