A study of frequency selection characteristics of negative conductivity in high temperature plasma

Abstract

Abstract The transmission characteristics of electromagnetic wave in a high temperature plasma slab are investigated by using transfer matrix method in this paper. The phenomenon of negative conductivity that emerged from high temperature plasma is investigated. The absorption of high temperature plasma is negative in the corresponding frequency band where the negative conductivity appears. According to the law of energy conservation, the sum of the reflection and transmission of electromagnetic waves in this frequency band will be greater than 1. That is, there should be an anomalous transmission phenomenon. According to the research, anomalous transmission is found in right-handed circular polarizations (RCP), while left-handed circular polarizations (LCP) do not occurred the similar phenomenon. In our study, it shows that the anomalous transmission is affected by external magnetic field, and different external magnetic field corresponding to different transmission frequencies. In the same time, the transmission frequencies move towards high band with the increasing of the magnetic field. Therefore, the negative conductivity and anomalous transmission can be artificial controllable. So, it can be used as a gain medium at a specific frequency or as an effective way to transmit information by frequency selection.