  We study laser driven spin-current effects at
ferromagnet/topological-insulator interfaces by two complementary experimental
approaches. The DC photocurrent is studied in ferromagnet/topological-insulator
bilayers with high spatial resolution. Dynamic interface currents are explored
via the emission of terahertz radiation emitted by these currents with high
temporal resolution. From our experiments, we reveal a lateral and dynamic
interaction of the ferromagnet and the topological insulator interface.
