# Spin-current diode with a monoaxial chiral magnet

## TL;DR

This paper demonstrates that monoaxial chiral magnets in a conical magnetic state can act as spin-current diodes, exhibiting nonreciprocal spin transport controllable by magnetic field and spin texture parameters.

## Contribution

It introduces a theoretical model showing how chiral conical magnetic states enable nonreciprocal spin transport, functioning as a controllable spin-current diode.

## Key findings

- Nonreciprocal spin transport depends on chirality, period, cone angle, and spin polarization.
- Distinct cone angle effects observed between long and short period spin textures.
- Nonreciprocity linked to spin states of itinerant electrons near leads.

## Abstract

Monoaxial chiral magnets exhibit a chiral conical magnetic state in a magnetic field parallel to the chiral axis. The conical spins carry the potential for nonreciprocal transport phenomena, as they break both spatial inversion and time reversal symmetries. Here we study the spin-dependent transport in the chiral conical magnetic state, using the Landauer method based on Green's functions for a one-dimensional Kondo lattice model. We show that the system exhibits nonreciprocal spin transport, which depends on the chirality, period, cone angle, and the polarization of the spin current. In particular, we find the distinct cone angle dependence between the spin textures with long and short periods. We also show that the nonreciprocity is related with the spin states of itinerant electrons near the leads. Our results indicate that the chiral cone acts as a spin-current diode, which can be flexibly controlled by a magnetic field.