Multifractal analysis on disordered superconductors under magnetic fields

Multifractality is one of the main characteristics of the Anderson transition [1]. It is also found in several disordered superconducting materials such as monolayer niobium dichalcogenides [2]. While these results are mainly focused on the multifractal behavior of the local density of states (LDOS) this analysis has not been shown for the superconducting gaps yet. Therefore, in this talk we attempt to reveal the multifractal behavior of not only the LDOS but also superconducting gaps based on numerical simulations in real space along with scanning tunneling microscopic (STM) measurement for Fe-based superconductors. Analyzing the distribution functions and the multifractal spectrum both for LDOS and superconducting gaps, we observed that Bogoliubons become Anderson-delocalized under magnetic fields.