PhotoEmission Electron Microscopy (PEEM) is a non-destructive imaging technique that involves shining linearly or circularly polarised X-rays onto the surface of a sample to provide spectroscopic information on a nm scale. This information can be used to study nanostructures significant for sensors, catalysts, magnetic materials and nanoscale devices and phenomena such as nanomagnetism.
Benefits of Synchrotron Techniques
Laboratory-based imaging techniques such as STM, AFM and TEM are capable of resolving nanostructures but, (apart from a limited capacity with STM), are unable to provide spectroscopic information. PEEM can link structure to function by providing spectroscopic data on a nm scale. The well-defined and variable polarisation state of synchrotron radiation can also provide, via dichroism, a contrast mechanism for imaging different magnetisations in ferromagnetic and antiferromagnetic nanostructures.
Applications
PEEM can be used to study the phenomenon of exchange bias, which has revolutionised the capabilities of magnetic information storage discs, but the underlying physical mechanisms are not well understood. There are also applications in the study of nano-particle catalysis, magnetic domain interactions and the characterisation of the properties of natural materials, such as chemical composition, local environment and phase identification. The fabrication and modification of novel materials on a nm scale is another important area.