There is much activity in condensed matter physics to look for new materials where superconductivity and ferromagnetism coexist, as this can suggest the presence of exotic new forms of superconductivity (or other novel quantum states). Conventional (BCS) superconductivity involves the formation of Cooper pairs of electrons having zero net spin-(S=0, spin-singlet) and orbital- (l=0, s-wave) angular momentum. Ferromagnetism and superconductivity are often mutually exclusive since the exchange field due to magnetic ions in a ferromagnetic metal favours a parallel alignment of the electrons, constituting a paramagnetic ‘pair breaking’ influence on the superconductor. True coexistence of ferromagnetism and superconductivity implies some ‘unconventional’ form of superconductivity, such as spin-triplet (S=1) superconductivity, in which the spins of a Cooper pair prefer to be aligned parallel rather than antiparallel.
One way to try and engender such exotic states of matter is to grow artificial materials by depositing very thin superconducting and ferromagnetic films (a few nm thick) on top of one another. In this way the properties of the final structure can be tuned, sometimes leading it to exhibit behaviours that have never been found in naturally occurring bulk materials. The production of artificial materials can be taken a step further if one also patterns such thin film materials in the plane of the film using advanced electron beam lithography technology. Such an approach could lead not only to the discovery of interesting new quantum phases, but could also to useful properties that could be exploited in future technologies, such as quantum computing.
In this project we have brought together a team of experts with a diverse range of skills that can grow, pattern, measure and undertake theoretical studies on the type of nanostructured materials discussed above. One particularly novel aspect of our approach is the use of powerful imaging techniques involving neutron, muons, X-rays and bespoke scanning magnetic sensors to gain unique insights into both the basic physics at play in systems exhibiting odd-frequency triplet superconductivity as well as the relation between the detailed magnetic and physical structures and their exotic properties.
In the initial part of the project we have collected extensive neutron. Muon and x-ray data. The PDRA will work on the analysis of this data and contribute to the experimental programme contained within the project.
As the projects contains world class expertise in all aspects of the materials discovery pipeline (material growth, fabrication, characterisation and theory) there are excellent opportunities for training and professional development both within ISIS and the wider project.
List of Duties / Work Programme / Responsibilities
A full-time vacancy exists as a post-doctoral researcher within the nanomagnetism research group which resides within the large scale structures group. The group has a 12 month position in the EPSRC funded project: Novel Coherent Electronic States in Artificial Ferromagnetic-Superconducting Hybrid Metamaterials. The project is part of a consortium consisting of St. Andrews, Leeds, Bath and Royal Holloway
In addition to the project the nanomagnetism group has strong collaborative research projects in a wide range of superconductivity and magnetism across the periodic table. The post is focused on exploiting neutron (and complementary) techniques to provide a quantitative nanoscale understanding of triplet superconducting materials. For the successful candidate, the position represents an excellent opportunity to develop both collaborative and personal scientific research programmes exploiting the capabilities of reflectometry (and complementary techniques) in the areas of nanoscale superconductivity and/or magnetism.
Contacts and Communication
You will interact extensively with visitors both from higher education institutions and industry. External representation will involve presentation of their scientific work at conference.
Personal Skills and Attributes
The position requires • A PhD in hard condensed matter specifically in superconductivity and/or nanoscale magnetism or extensive relevant experience. • Further post-doctoral experience is desirable but not essential. Practical experience of neutron or X-ray techniques in superconductivity/magnetism is essential. • Practical experience of polarised neutron reflectivity data analysis is essential. • Good interpersonal and presentation skills are also required.