Group delay compensation based on negative group velocity effect of spoof surface plasmon polaritons

Abstract

Abstract Negative group velocity (NGV) exists only in the anomalous dispersion band with resonance absorption. In this paper, it is verified that spoof surface plasmon polaritons (SSPPs) with spiral-shaped periodic units have the NGV characteristics near cutoff frequency. The negative group delay of this NGV SSPP can be used to achieve the compression of the pulse signal, and also to compensate the positive group delay with high efficiency. Of course, this group delay compensation scheme based on NGV may introduce an absorption loss, which is the characteristic of all passive negative group delay circuits.