文摘
A quasi-optical transmission-meter is employed to measure the performance of gold nanoparticle dispersions at the W-band (75-110?GHz). A specifically designed liquid sample holder was integrated into the transmission-meter to secure reliable measurement repeatability and an iterative method was utilized to retrieve the dielectric properties from the measured transmission coefficients. Different to some previous results in MHz and GHz range, it was found that the dielectric properties of purified gold nanoparticle (GNP) dispersions did not exhibit marked difference to that of DI-water, which suggests a weak interaction of GNP with EM radiation in the W-band, consistent to the predictions from the effective medium theory and microscopic views. Further work is proposed to explore the dielectric properties of GNP dispersions in the shorter wavelength, such as sub-terahertz, terahertz and infrared range.