Controlling polarization of spintronic THz emitter by remanent magnetization texture

Terahertz (THz) sciences and technologies have contributed to a rapid development of wide range applications expanded the frontiers in fundamental science. Spintronic terahertz emitters offer conceptual advantages since spin orientation magnetic layer can be easily controlled either by externally applied field or internal distribution determined specific shape elements. Here, we report switchable source based on micropatterned heterostructures driven femtosecond laser pulses. We show that precise tunability polarization state is facilitated underlying magnetization texture dictated microstructure. These results also reveal physical mechanisms nonuniform generation ultrafast currents heterostructures. Our findings indicate emission linearly polarized THz waves switched off saturating sample using biasing field, opening fascinating perspectives for integrated on-chip devices with wide-ranging potential applications.