1：Experimental Design and Method Selection:

The study involves the design of a hybrid THz emitter combining spintronic devices with semiconductor materials to enhance THz emission, particularly in the lower frequency range (0.1–0.5 THz). The methodology includes the use of the inverse spin Hall effect (ISHE) in magnetic heterostructures and photoconduction in semiconductors.

2：1–5 THz). The methodology includes the use of the inverse spin Hall effect (ISHE) in magnetic heterostructures and photoconduction in semiconductors. Sample Selection and Data Sources:

2. Sample Selection and Data Sources: High-resistivity silicon (HR-Si) substrates with Pt or W (6 nm)/Co (3 nm) bilayers were used. The samples were prepared by magnetron sputtering and patterned using photolithography and Ar ion beam etching.

3：List of Experimental Equipment and Materials:

A THz time domain spectroscopy (TDS) system, an 800 nm fs laser pump, a probe beam, a wire grid THz polarizer, and a delay generator for synchronized current pulses were used.

4：Experimental Procedures and Operational Workflow:

Measurements were performed at room temperature with the laser incident on the devices from the HM/FM film side. A pulsed current was applied through the wires, synchronized to the pump laser pulses, to minimize current-induced heating.

5：Data Analysis Methods:

The THz signals were analyzed in both time and frequency domains, with fast Fourier transform (FFT) spectra used to observe enhancements in the lower THz frequency range.