The transmission enhancement of a THz pulse through an Ag/Ag2O layer detected by terahertz time-domain spectroscopy

This paper reports a new way to detect the enhanced transmission of aTHz electromagnetic wave through an Ag/Ag$_{2}$O layer by THz-TDS(time-domain spectroscopy). As the THz beam illuminates thesub-wavelength Ag particles gained by Ag$_{2}$O thermaldecomposition, the evanescent wave is generated. The evanescent waveis coupled by a 500$mu $m-GaAs substrate, which attaches behind theAg/Ag$_{2}$O layer, and then it transmits to the far field to bedetected. The experimental results indicate that the transmittingamplitude is enhanced, as well as the frequent shifting and spectrabroadening.