Flexible Spintronics and Magnetic Properties

Flexible spintronics merges the control of electron spin with bendable electronic platforms, enabling lightweight, conformable devices that retain robust magnetic functionality under mechanical deformation. Central to this field are magnetic thin films and nanostructures engineered for reliable anisotropy, magnetoresistance and interlayer coupling on polymeric or ultrathin silicon substrates. Key phenomena include magnetoelastic coupling, which links mechanical strain to magnetic anisotropy, and spin‐dependent transport effects such as tunnel magnetoresistance. Device classes span magnetic tunnel junctions, spin valves, synthetic antiferromagnets and microwave resonators, all tailored for curvature tolerance. Advances address challenges of preserving high magnetoresistive ratios, stable switching fields and low damping during repeated bending, while unlocking applications in wearable sensors, non-volatile memory, tactile interfaces and energy-efficient logic for the Internet of Things and biomedical monitoring.

Research from Nature Portfolio

Magnetostrictive FeGa films deposited on flexible Kapton substrates have been shown to exhibit strain-tunable uniaxial anisotropy, with convex and concave bending states modulating coercivity and revealing exchange-bias effects at cryogenic temperatures, thus demonstrating potential for adaptive magnetoelastic sensors. Investigations into the anomalous Nernst effect in flexible magnetostrictive films combined analytical models of induced uniaxial and magnetoelastic anisotropy with experiments under external stress, achieving quantitative agreement on stress-dependent thermoelectric voltage and validating a predictive framework for thermomagnetic transduction. Controlled bending of spin-valve stacks on polymer substrates has further enabled reversible enhancement or diminution of magnetic anisotropy in free and pinned layers, culminating in prototype flexible sensor arrays capable of detecting magnetic microbeads with minimal performance degradation.

Flexible Spintronics and Magnetic Properties publication trend

The graph below shows the total number of articles in flexible spintronics and magnetic properties across all publications each year (not limited to Nature Index journals).

Technical terms

Spintronics: Exploitation of electron spin, alongside charge, to encode and manipulate information in solid-state devices.

Magnetic anisotropy: Directional dependence of a material’s magnetic energy, dictating preferred orientations of magnetisation.

Magnetoelastic coupling: Interaction between mechanical strain and magnetic properties, enabling control of anisotropy via deformation.

Tunnel magnetoresistance (TMR): Variation in electrical resistance of a magnetic tunnel junction as the relative orientation of magnetisation in its electrodes changes.

Magnetic tunnel junction (MTJ): A sandwich of two ferromagnetic layers separated by an ultrathin insulating barrier that permits spin-dependent quantum tunnelling.

Ferromagnetic resonance (FMR): Resonant absorption of microwave radiation by a ferromagnet under an applied magnetic field, used to characterise dynamic magnetic properties.

References

1. Magnetic Properties of Amorphous Ta/CoFeB/MgO/Ta Thin Films on Deformable Substrates with Magnetic Field Angle and Tensile Strain. Sensors (2023).
2. Anomalous Nernst effect in stressed magnetostrictive film grown onto flexible substrate. Scientific Reports (2019).
3. Magnetic properties of FeGa/Kapton for flexible electronics. Scientific Reports (2022).
4. CoFeB/MgO-based magnetic tunnel junction directly formed on a flexible substrate. Applied Physics Express (2019).
5. A Strategy to Modulate the Bending Coupled Microwave Magnetism in Nanoscale Epitaxial Lithium Ferrite for Flexible Spintronic Devices. Advanced Science (2018).
6. Magnetization Manipulation of a Flexible Magnetic Sensor by Controlled Stress Application. Scientific Reports (2018).