Spin Transport Phenomena in Magnetic Materials

In magnetic materials, transport of spin angular momentum underpins emerging technologies in data storage and logic beyond traditional charge-based electronics. Spin transport encompasses the flow of spin currents—fluxes of spin polarization either carried by conduction electrons or by collective excitations known as magnons. In metals and semiconductors, spin Hall and inverse spin Hall effects interconvert charge and spin currents via spin–orbit coupling, enabling efficient generation and detection of spin accumulation at interfaces. In magnetic insulators, magnons propagate spin without an accompanying charge current, affording long-distance, low-loss transmission. The efficiency of spin transport is governed by magnetic damping, interfacial spin mixing conductance and the symmetry of spin–orbit effects. Antiferromagnets and two-dimensional van der Waals magnets have recently expanded the palette of spin channels, offering novel polarisation degrees of freedom and tunable anisotropies. These discoveries have led to applications in non-volatile magnetic memories, magnonic logic gates and spin caloritronic devices, with room-temperature operation and energy-efficient switching presenting global engineering opportunities.

Research from Nature Portfolio

Recent studies have demonstrated efficient spin pumping from two-dimensional ferromagnets into heavy metals, achieving record low magnetic damping and high interfacial spin transmission efficiency in van der Waals Cr2Ge2Te6 heterostructures, indicating their promise for coherent spin sources in low-temperature spintronic devices. Investigations into canted antiferromagnets have revealed anisotropic long-range magnon transport in YFeO3, where the Dzyaloshinskii–Moriya interaction and applied fields enable decay lengths of several hundred nanometres, highlighting new mechanisms in noncollinear spin structures. Moreover, artificial ferrimagnetic multilayers have been used to control magnon chirality, showing that alternating Py/Gd stacks permit switching and detection of right- and left-handed spin wave modes, thus establishing chirality as an independent information carrier for next-generation magnonic platforms.

Spin Transport Phenomena in Magnetic Materials publication trend

The graph below shows the total number of articles in spin transport phenomena in magnetic materials across all publications each year (not limited to Nature Index journals).

Technical terms

Spin current: A flow of spin angular momentum, carried by electrons or magnons, without net charge transfer.

Magnon: A quantised collective excitation of spin waves in an ordered magnetic lattice acting as a spin carrier.

Spin Hall effect: The lateral deflection of spin-polarised electrons by spin–orbit coupling, converting charge current to transverse spin current.

Inverse spin Hall effect: The reciprocal process where a spin current generates a detectable transverse voltage.

Spin pumping: The generation of a spin current from the dynamic precession of a magnetisation into an adjacent non-magnetic layer.

Spin–orbit torque: A torque on the magnetisation resulting from spin accumulation induced by an in-plane charge current in heavy-metal/ferromagnet bilayers.

Dzyaloshinskii–Moriya interaction: An antisymmetric exchange interaction that favours non-collinear spin textures and influences magnon dispersion.

Spin mixing conductance: A parameter quantifying the efficiency of spin current transfer across a magnetic/non-magnetic interface.

References

1. Electrical detection of spin pumping in van der Waals ferromagnetic Cr2Ge2Te6 with low magnetic damping. Nature Communications (2023).
2. Anisotropic long-range spin transport in canted antiferromagnetic orthoferrite YFeO3. Nature Communications (2022).
3. Switching magnon chirality in artificial ferrimagnet. Nature Communications (2022).
4. Enhanced spin–orbit torque via interface engineering in Pt/CoFeB/MgO heterostructures. APL Materials (2019).
5. Origin of the magnetic spin Hall effect: Spin current vorticity in the Fermi sea. Physical Review Research (2020).
6. Spin transport in antiferromagnetic insulators: progress and challenges. NPG Asia Materials (2019).