Final Report Summary - NAMASTE (Nanostructured Magnetic Materials for Nanospintronics)
Executive summary:
Spintronics is a key area of condensed matter research which is of both great fundamental and practical importance. It has already revolutionised magnetic storage technologies and delivered the first commercial non-volatile RAM chips. Spintronics has the potential to supersede existing storage and memory applications, and to provide alternatives to current CMOS technology. It offers the promise of future information processing in which all key components including storage, memories, processors, and optoelectronics devices are based on spin and integrated within one solid-state device.
The NAMASTE project was a very ambitious and extensive integrated theoretical, experimental and technological programme of research based on radical new approaches the engineering and manipulation of magnetism which aimed in particular to achieve electrical control of magnetism to realize new types of spintronic devices.
The quality of the research carried out within NAMASTE has been very high. It has lead to a number of significant breakthroughs which have been reported in many major publications in the highest impact journal within physics such as the Nature journals and Physical Revive Letters. The work of NAMASTE has been reports in very many invited conference presentation.
Among the main achievements of the project have been:
- Significant advances in the theoretical approaches to the calculation of magnet and magnetotransport properties of magnetic materials, heterostructures and devices.
- The development of high quality magnetic semiconductor, hybrid metal / semiconductor, and ferromagnetic metal / piezoelectric stacks and the atomic scale characterisation of these materials.
- The demonstration of the ability to fully control local anisotropies in ferromagnetic nanostructures by local strain engineering and the development of a full quantitative understanding of this effect through ultra high resolution structural characterisation and theoretical modelling.
- The demonstration of the ability to control magnetisation orientation and domain wall dynamics in ferromagnetic semiconductor devices through piezo-electric strain.
- The achievement of strong piezo-electric strain control of coercive field in ferromagnetic metal / piezoelectric stacks and the first demonstration of voltage induced, non-volatile switching of the magnetisation in a metal in zero magnetic field and at room temperature (via piezo-strain).
- The achievement of strong non-volatile electrostatic gate control of coercive fields in ferromagnetic semiconductors devices and the demonstration of charge-mediated ferroelectric control of magnetic domain-wall propagation and domain structures.
- The discovered of a new physical effect: current induced ferromagnetic resonance and used this to measure the magnetic anisotropy constants of individual magnetic nanostructures.
- The elucidation of the nature of the Coulomb blockade anisotropic magnetoresistance effect, and the first measurements of the chemical potential anisotropies of a ferromagnetic material.
- The first demonstrations of the tunnelling anisotropic magnetoresistance effect at room temperature and of this effect in antiferromagnetic devices.
- The development of a model of gate voltage triggered fast precessional switching and the realisation of a p-i-n device in this should be realisable (but not yet the demonstration of this effect).
- The development of a architecture in which piezo-strain triggered fast magnetisation switching should be realisable (but not yet the demonstration of this effect).
Spintronics is a key area of condensed matter research which is of both great fundamental and practical importance. It has already revolutionised magnetic storage technologies and delivered the first commercial non-volatile RAM chips. Spintronics has the potential to supersede existing storage and memory applications, and to provide alternatives to current CMOS technology. It offers the promise of future information processing in which all key components including storage, memories, processors, and optoelectronics devices are based on spin and integrated within one solid-state device.
The NAMASTE project was a very ambitious and extensive integrated theoretical, experimental and technological programme of research based on radical new approaches the engineering and manipulation of magnetism which aimed in particular to achieve electrical control of magnetism to realize new types of spintronic devices.
The quality of the research carried out within NAMASTE has been very high. It has lead to a number of significant breakthroughs which have been reported in many major publications in the highest impact journal within physics such as the Nature journals and Physical Revive Letters. The work of NAMASTE has been reports in very many invited conference presentation.
Among the main achievements of the project have been:
- Significant advances in the theoretical approaches to the calculation of magnet and magnetotransport properties of magnetic materials, heterostructures and devices.
- The development of high quality magnetic semiconductor, hybrid metal / semiconductor, and ferromagnetic metal / piezoelectric stacks and the atomic scale characterisation of these materials.
- The demonstration of the ability to fully control local anisotropies in ferromagnetic nanostructures by local strain engineering and the development of a full quantitative understanding of this effect through ultra high resolution structural characterisation and theoretical modelling.
- The demonstration of the ability to control magnetisation orientation and domain wall dynamics in ferromagnetic semiconductor devices through piezo-electric strain.
- The achievement of strong piezo-electric strain control of coercive field in ferromagnetic metal / piezoelectric stacks and the first demonstration of voltage induced, non-volatile switching of the magnetisation in a metal in zero magnetic field and at room temperature (via piezo-strain).
- The achievement of strong non-volatile electrostatic gate control of coercive fields in ferromagnetic semiconductors devices and the demonstration of charge-mediated ferroelectric control of magnetic domain-wall propagation and domain structures.
- The discovered of a new physical effect: current induced ferromagnetic resonance and used this to measure the magnetic anisotropy constants of individual magnetic nanostructures.
- The elucidation of the nature of the Coulomb blockade anisotropic magnetoresistance effect, and the first measurements of the chemical potential anisotropies of a ferromagnetic material.
- The first demonstrations of the tunnelling anisotropic magnetoresistance effect at room temperature and of this effect in antiferromagnetic devices.
- The development of a model of gate voltage triggered fast precessional switching and the realisation of a p-i-n device in this should be realisable (but not yet the demonstration of this effect).
- The development of a architecture in which piezo-strain triggered fast magnetisation switching should be realisable (but not yet the demonstration of this effect).