Hybrid Co/2D-WSe2-based THz spintronic emitter with tunable polarization

We demonstrate an efficient THz spintronic emitter using a Co/WSe2 heterostructure that enables direct control of the emitted THz polarization. The device is excited by femtosecond laser pulses and leverages spin-to-charge conversion at the Co/WSe2 interface to generate broadband THz pulses. We observe that the THz emission polarization can be continuously tuned via the magnetization orientation without significant loss in intensity. At higher pump fields, nonlinear optical effects in the WSe2 layer contribute to the THz output, indicating an emission enhancement beyond the conventional spintronic mechanism.