Propagation of electromagnetic energy is fundamental in our 'information age' modern world. It is evident from the fundamental Maxwell's equations, and his wave equation, that what determines propagation is the dielectric permittivity and magnetic permeability of the materials that the wave/energy propagates in, or interacts with. Therefore, control and manipulation of permitivitty and permeability is essential to optimise performance and open up new applications.
We already investigate the inherent electromagnetic properties of magnetic materials in the 0.5-20 GHz regime, paying particular attention to the permeability, as we seek to tune it by creating 'synthetic' materials by 'multilayering' known materials to create new functionality not achievable from the constituents themselves. In the application of data storage, as operational frequencies increase, and the temperature in portions of a read/write head of a hard-disk drive may vary, control of permeability is necessary to optimise magnetic shielding from the reading and writing processes.
However, there are many other applications where control over electromagnetic properties such as permeability are vital e.g. devices such as filters, phase shifters, and signal to noise enhancers. These microwave devices are widely used in radar systems and in both military and civilian communication systems where the majority of thin film systems for electronic devices are on rigid substrates such as silicon/ceramic wafers.
This project will extend the interest in the development of these synthetic magnetic systems with controlled permeability onto flexible substrates. Despite many fundamental scientific challenges of preparing materials on flexible and even transparent substrates there is major international effort in flexible electronics particularly for display systems e.g. electronic paper. Flexible substrates offer the opportunity to coat or cover surfaces that could be used in RF and microwave applications such as shielding or reflection. The security sector also offers major opportunities with smart tagging (bank notes, commodities) or radio frequency identification tags (secure access).
This project will be aimed at developing a series of materials deposited on flexible substrates that can be explore for different applications and though the duration of the project the student will have the opportunity to engage and interact with other industry end users who might exploit the research into applications described above.