Director of Undergraduate Teaching
MA University of Cambridge
PhD University of Cambridge
Functional Thin Films
My work within the Device Materials Group focuses on the fabrication, modelling and microstructural and electromagnetic characterization of functional thin-film materials, in particular superconducting wires and tapes.
Functional thin-film growth
We are interested in optimizing the growth parameters of thin films in order to optimize their functional properties. One example of this is the development of buffer layers and superconducting films for coated conductor tapes. A crucial factor in improving the performance of these materials is a firm understanding of how epitaxial growth occurs for different thin-film deposition methods.
Characterisation of superconductors
In order to be commercially viable, superconducting wires must be able to carry substantial currents in magnetic fields. We aim to understand how the microstructure of the superconducting layer in a coated conductor tape determines its maximum current. This is achieved by characterizing the microstructure of films using techniques such as XRD and EBSD in parallel with measurement of the electromagnetic properties of the tapes.
Modelling superconducting current flow
We aim to understand how the microscopic influence of grains and grain boundaries in superconductors determines the macroscopic properties of wires and tapes. We develop mesoscale network models in order to discover which properties are the most important in limiting the performance, depending on the conditions of temperature and magnetic field appropriate to the application. An understanding of the statistical variations of properties within these materials and of the dependence of such variations on processing is required in order to determine the most effective wire configuration.
|Schematic of a coated conductor - a stack of thin films on a metallic substrate
- W Zhai, YH Shi, JH Durrell, AR Dennis, NA Rutter, SC Troughton, SC Speller & DA Cardwell, "The processing and properties of single grain Y–Ba–Cu–O fabricated from graded precursor powders" Supercond. Sci. Technol. 26 125021 (2013)
- M Weigand, NA Rutter & JH Durrell, "In-plane critical current density measurements of straight and curved tracks in RABiTS-MOD coated conductors" Supercond. Sci. Technol. 26 105012 (2013)
- JH Durrell & NA Rutter, "Importance of low-angle grain boundaries in YBa2Cu3O7−δ coated conductors" Supercond. Sci. Technol. 22 013001 (2009).