Controlling the propagation of terahertz(THz)wave is very important in the application of THz technology. THz modulator is considered to be the key device in next-generation THz wireless communication. A new-type opticallypumpedTHz modulator based on Si-grown monolayer tungsten disulfide(WS2)was demonstrated. WS2acts as acatalystdue to the formation ofheterojunction at the junction between Si substrate and WS2,since more carriers are catalyzed at the heterojunction under pumping power,the modulator can achieve more deep modulation depth. The result shows that the modulation depth of this Si-grown monolayerWS2modulator can reach63.6% under the low pumping power of117 mW andthe wavelength ofthe pumplightis 660 nm. This noveltwo-dimensionaltransi-tion metal dichalcogenides with high modulation efficiency have a great prospect in the application of THz technology.动计划(17ZR1448300)