Nano structure enabled extreme light-matter interactions

This experimental physics project will mainly be concerned with using ultrafast optical techniques at terahertz frequencies to explore the highly non-equilibrium dynamics of strongly driven electrons and lattice vibrations in materials which are of interest from either a technological or fundamental viewpoint. Examples include materials displaying metal-insulator transitions, low dimensionality, unconventional superconductivity or coupling between electric and magnetic properties (multiferroics). The common theme is that these are complex systems where the theoretical explanation for the material properties is often incomplete or contested and where the study of strong light-matter interactions in previously uncharted regions of parameter space could help develop understanding of the equilibrium properties or reveal new phenomena such as breakdown of the effective mass approximation, optical gain and previously unknown transient phases.

An intense source of terahertz radiation has been constructed in Bath for non-equilibrium investigations using the pump-probe ultrafast technique but we wish to build on this and increase the available driving field in samples by an order of magnitude in order to explore more extreme light-matter interactions. We believe that this can be achieved by concentrating the pump radiation using energy harvesting nanoscale structures. For example non-resonant enhancement could be engineered using arrays of slits in thin metal films and resonant enhancement could be enabled by arrays of metallic antenna-like structures. Such arrays can be manufactured with the aid of optical interference or electron beam lithography techniques that are available in Bath and in collaborating institutions. Designs can be optimised using standard electromagnetic modelling software and preliminary testing can be performed on relatively simple semiconducting materials before application to more complex materials.

The project will offer opportunities to develop skills and experience in ultrafast optical measurements, photonics, computer modelling, nano-fabrication and materials physics.

Applicants should have an interest in experimental condensed matter research and photonics and have, or expect to gain, a First or good Upper Second Class Honours degree in physics (or equivalent international qualification).

Informal enquiries are welcomed and should be directed to Dr Steven Andrews, [Email Address Removed].

Formal applications should be made via the University of Bath’s online application form for a PhD in Physics:
https://samis.bath.ac.uk/urd/sits.urd/run/siw_ipp_lgn.login?process=siw_ipp_app&code1=RDUPH-FP01&code2=0013

More information about applying for a PhD at Bath may be found here:
http://www.bath.ac.uk/guides/how-to-apply-for-doctoral-study/

Anticipated start date: 30 September 2019.