Using Magnetic-Field-Controlled Ferrofluid as a THz Wave Emitter

We characterize the THz wave emission from ferrofluid under fs-laser pulse excitation. The controllability of the radiation by an external magnetic field is demonstrated. In addition to the magnetic field, the ferrofluid concentration also impacts intrinsically the generated THz wave. The results are contrasted against other established sources with a similar excitation scheme to delineate ferrofluid's THz radiator capacity.