Project Title: Superstructures in lithium cobaltate
Project Supervisor: Professor Jon Goff
"Working for six weeks with the condensed matter group at Royal Holloway I had an awesome time. The main aim of this placement was to grow crystals of different compositions using the optical floating zone furnace, study their structure with the help of X-rays and modelling software before testing their thermoelectric properties with the use of the Physical Properties Measurement System (PPMS). The crystals which were grown during my internship were two pure Sodium Cobaltate crystals, for study using neutron diffraction at facilities such as ISIS, and three Manganese doped Sodium Cobaltate crystals with varying Sodium content. Doping of materials alters their thermoelectric properties thus making them very interesting to study. Good thermoelectric materials, with a high figure of merit, are highly sought after as they have a strong potential to be used in industry in applications such as the direct cooling of components in computers which will push back the limit of Moore's law and enable us to achieve more processing power or "more Moore" as its been called!
Another part of my internship included carrying out experiments on Calcium doped Sodium Cobaltate crystals using the PPMS to measure their thermoelectric properties such as the thermal conductivity, Seebeck coefficient and resistivity while varying the temperature from which we could then work out the figure of merit of the material.
I also carried out several X-ray diffraction measurements on various crystals of different compositions to check for superlattice peaks as well as doing a little bit of work with the modelling software, MatLab, to try to determine the structure of the beta phase of Strontium doped Sodium Cobaltate.
All of this was really enjoyable as I was able to get some hands on experience doing practical physics work as well as getting a little bit of experience with the theoretical side while working with the modelling software.
Overall I had a great time and feel that this was a very positive experience as I got the opportunity to learn several new things, not only about this particular area of physics, but also about what physics research is like in general. As well as this, it was a highly engaging and fun job where I got to work in a very calm and relaxed atmosphere with some really nice, friendly and helpful people. Another advantage of doing a summer placement as far as I can see, is that not only do you get to do some fun physics, but it also looks good on your CV and I would really recommend anyone who is interested in doing physics later on in their career to give it a go!"