Spintronics and spin-caloritronics in magnetic nanosystems

Nano-scale magnetic technologies could be used in applications as diverse as high-density low-power data storage and more sensitive diagnostic tools for bio-sensing. Understanding the motion of magnetic regions in nanowires and how interactions of electron spins and thermal gradients effect the wires magnetic properties are key. Researchers need robust measurement methods for reliably characterising fundamental quantum material properties as a precursor to introducing electron spin technologies into new applications.

The project Spintronics and spin-caloritronics in magnetic nanosystems (SpinCal) developed and characterised several magnetic nanodevices. These were then used to generate an understanding of the interplay of spin-polarised transport and thermal gradients within the devices.

The project:

• Optimised fabrication processes for magnetic boundaries in nano-devices and performed detailed spin characterisations over a broad temperature range.
• Characterised the efficiency of thermo electrical power generation in spintronic devices for the first time and found that the thermo electrical efficiency can be changed by more than 60% when magnetisation is reversed.

The fundamental research performed in this project has introduced measurement reliability for the interaction of electron spins and heat currents and has enabled the first international comparison of these types of measurements. Coupled with the discovery of thermo-electric power changes with reversal of magnetic field direction, there is now the potential for using this phenomena in susceptible materials for the external operation of electronic devices without the need for connections.

The methods developed in the project provide best practice for generating reliable measurements for spintronics and thermal effects. The IEC Technical Committee, Nanotechnologies for standardisation of nano-scale magnetic field measurements, has started drafting a new measurement standard in this emerging technological field. The EURAMET EMPIR project Nano-scale traceable magnetic field measurements is continuing to support measurement research in this field.