We investigate transport in a superconducting nanostructure housing a Weyl
point in the spectrum of Andreev bound states. A minimum magnet state is
realized in the vicinity of the point. One or more normal-metal leads are
tunnel-coupled to the nanostructure. We have shown that this minimum magnetic
setup is suitable for realization of all common goals of spintronics: detection
of a magnetic state, conversion of electric currents into spin currents,
potentially reaching the absolute limit of one spin per charge transferred,
detection of spin accumulation in the leads. The peculiarity and possible
advantage of the setup is the ability to switch between magnetic and
non-magnetic states by tiny changes of the control parameters: superconducting
phase differences. We employ this property to demonstrate the feasibility of
less common spintronic effects: spin on demand and alternative spin current.Comment: 9 pages, 6 figure