Structure and dynamics of a pinned vortex liquid in a superconducting a−Re6Zr thin film

Real space imaging using a scanning tunnelling microscope reveals the formation of an inhomogeneous vortex liquid state in few nanometer thick superconducting films that does not freeze into a crystal or a glass down to 0.41 $K$. Vortices in this two-dimensional liquid form a network of percolating paths, due to the combined effect of pinning and intervortex interaction. While some vortices remain static, others move on this network, with their relative fractions changing with magnetic field, temperature, and applied current.