Final Report Summary - DYNASYNC (Dynamics in Nano-scale Materials Studied with Synchrotron Radiation)
The overall objective of the 'Dynamics in nano-scale materials studied with synchrotron radiation' (Dynasync) project is to increase the basic understanding of dynamic phenomena and in particular of their size dependence in nanostructures. The combination of nuclear resonant scattering experiments with advanced surface sensitive experimental and computational methods yields detailed insights into the following areas:
- The modification of collective excitations like phonons by interfaces and boundaries in thin films, multilayers, and nanoparticles.
- The role of diffusion in the kinetics of structural changes that occur during processing of materials or the growth of thin films.
- The dynamical magnetic properties of nanostructures, the evolution of magnetic properties during growth and the interlayer coupling of magnetic layers, as they determine the fast magnetisation reversal and the ultimate magnetic storage density.
Work performed and results achieved
One of the central activities in the frame of the Dynasync project was the development of an extended UHV system for in-situ investigations of surface nano-structures using the method of nuclear resonant scattering (NRS). Moreover, a portable UHV chamber was developed for in-situ grazing incidence small angle X-ray diffraction and photon correlation spectroscopy measurements.
Another key activity within the project was the development of a multi-APD array for spatially resolved NRS measurements. After commissioning of this new detector system, a first successful study on diffuse scattering from magnetic domains in thin films could be performed. Various characterisation techniques were also implemented in the partner laboratories in order to complement synchrotron radiation studies.
End results with intentions for use and impact
The methods and instruments developed within the Dynasync project open unique possibilities to simultaneously investigate a multitude of dynamical properties. New prospects are on the horizon allowing one to investigate the intimate relationship between magnetism or diffusion and lattice dynamics, correlated with structure and morphology. This is particularly interesting in the field of functional magnetic structures. It is obvious that physical properties of new devices will depend not only on their structural, but also on their dynamical properties.
Examples are nanoscale sensor / actuator systems that rely on the shape memory effect and nanoscale magnetostrictive devices. The performance of these systems will be strongly influenced by finite-size effects and the dimensionality of the system. The microscopic origin of these effects is by far not understood yet. A thorough understanding opens the way to tailor the development of future functional nanoscale systems.
Researchers expect the project to yield significant contributions to this field, stemming from the unique properties of the experimental method. A distinct advantage of the technique of nuclear resonant scattering is that it is isotope-specific. Compared to other methods, the signal is essentially free of contributions from surrounding materials. Moreover, probe layers can be selectively deposited to study the magnetic and dynamic properties with atomic resolution.
Nuclear resonant scattering of synchrotron radiation is practically only feasible at the specialised beam lines of modern third generation sources like the ESRF, APS and Spring-8. A major aspect of the project is the development of new sample environments and on-line characterisation techniques. The new methodology developed can be used to follow time dependent processes in real time.
Nuclear resonant scattering experiments can be performed in situ, under UHV conditions, during the formation process of the system (deposition, oxidation, annealing). It gives the unique structural, chemical or magnetic information on the properties evolution while the nanostructures are grown and modified.
The experimental facilities developed within the project are available for the international community in the field of nanoscience and technology. This will strengthen the leading role of the European partners for the integration of nanoscience into large-scale research facilities.
- The modification of collective excitations like phonons by interfaces and boundaries in thin films, multilayers, and nanoparticles.
- The role of diffusion in the kinetics of structural changes that occur during processing of materials or the growth of thin films.
- The dynamical magnetic properties of nanostructures, the evolution of magnetic properties during growth and the interlayer coupling of magnetic layers, as they determine the fast magnetisation reversal and the ultimate magnetic storage density.
Work performed and results achieved
One of the central activities in the frame of the Dynasync project was the development of an extended UHV system for in-situ investigations of surface nano-structures using the method of nuclear resonant scattering (NRS). Moreover, a portable UHV chamber was developed for in-situ grazing incidence small angle X-ray diffraction and photon correlation spectroscopy measurements.
Another key activity within the project was the development of a multi-APD array for spatially resolved NRS measurements. After commissioning of this new detector system, a first successful study on diffuse scattering from magnetic domains in thin films could be performed. Various characterisation techniques were also implemented in the partner laboratories in order to complement synchrotron radiation studies.
End results with intentions for use and impact
The methods and instruments developed within the Dynasync project open unique possibilities to simultaneously investigate a multitude of dynamical properties. New prospects are on the horizon allowing one to investigate the intimate relationship between magnetism or diffusion and lattice dynamics, correlated with structure and morphology. This is particularly interesting in the field of functional magnetic structures. It is obvious that physical properties of new devices will depend not only on their structural, but also on their dynamical properties.
Examples are nanoscale sensor / actuator systems that rely on the shape memory effect and nanoscale magnetostrictive devices. The performance of these systems will be strongly influenced by finite-size effects and the dimensionality of the system. The microscopic origin of these effects is by far not understood yet. A thorough understanding opens the way to tailor the development of future functional nanoscale systems.
Researchers expect the project to yield significant contributions to this field, stemming from the unique properties of the experimental method. A distinct advantage of the technique of nuclear resonant scattering is that it is isotope-specific. Compared to other methods, the signal is essentially free of contributions from surrounding materials. Moreover, probe layers can be selectively deposited to study the magnetic and dynamic properties with atomic resolution.
Nuclear resonant scattering of synchrotron radiation is practically only feasible at the specialised beam lines of modern third generation sources like the ESRF, APS and Spring-8. A major aspect of the project is the development of new sample environments and on-line characterisation techniques. The new methodology developed can be used to follow time dependent processes in real time.
Nuclear resonant scattering experiments can be performed in situ, under UHV conditions, during the formation process of the system (deposition, oxidation, annealing). It gives the unique structural, chemical or magnetic information on the properties evolution while the nanostructures are grown and modified.
The experimental facilities developed within the project are available for the international community in the field of nanoscience and technology. This will strengthen the leading role of the European partners for the integration of nanoscience into large-scale research facilities.
