Mr Alexander Blair
|Member of the Centre for Materials Physics|
(i) Simulations of polycrystalline superconductors in high magnetic fields
Critical current densities measured for high-field superconductors are typically less than 1% of theoretical limits. The critical current density has important consequences in technological applications such as in fusion energy, as imposes a major restriction on the size of the superconductors that may be used.
To investigate the mechanism that determines critical current density, we are using simulations on model polycrystalline superconductors based on time-dependent Ginzburg--Landau theory. By doing so we hope to visualise how magnetic flux flows through these systems and identify the pinning mechanism for some of the most commonly used materials.
(i) Analysis of the square flux-line-lattice in highly magnetic superconductors
The observed square flux-line-lattice (FLL) of highly magnetic superconductors is currently unexplained. We are investigating analytically whether this can be explained within the context of Ginzburg--Landau theory, or whether it needs extension to explain the shape of the FLL.
- Blair, Alexander & Hampshire, Damian (2019). Modeling the Critical Current of Polycrystalline Superconducting Films in High Magnetic Fields. IEEE Transactions on Applied Superconductivity 29(5): 8001705.
- Blair, Alexander Ian & Hampshire, Damian (2018). Time-Dependent Ginzburg-Landau Simulations of the Critical Current in Superconducting Films and Junctions in Magnetic Fields. IEEE Transactions on Applied Superconductivity 28(4): 8000205.