Deviations from the London model in superconductors
Using Small-Angle Neutron Scattering (SANS) we have studied the flux line lattices of the first heavy-fermion superconductor to be discovered, CeCu2Si2, the well-known high-temperature superconductor YBa2Cu3O7, along with Ca-doped variants of this compound, and several topological superconductor candidates that have attracted a lot of attention in the last few years, such as PbTaSe2, Au2Pb and β-B