Direct numerical simulations for non-equilibrium superconducting dynamics and related neutron detection in MgB₂

After the discovery of an alloy superconductor MgB₂, a quite unique application using MgB₂ has been suggested by Ishida et al. in terms of neutron detection. It is based on an intuitive idea that an energy released by the nuclear reaction between a neutron and ¹⁰B leads to an instantaneous destruction of the superconducting state and the moment is observable by the voltage jump under the current application. In this paper, we investigate how the nucleated normal region enlarges inside the superconductor with the heat diffusion and shrinks with quenching from the heat bath attached at the surface by performing direct numerical simulations for the time-dependent Ginzburg-Landau (TDGL) equation coupled with the Maxwell and the heat diffusion equations. We also measure how the superconducting current carrying states electromagnetically respond to the non-equilibrium dynamics in order to explore a condition in which the neutron detection is possible.