Terahertz meta-chip switch based on C-ring coupling.

Terahertz switch is one of the key components of future communication, radar, and imaging systems. Limited by the strong electromagnetic coupling in subwavelength scale, the traditional terahertz switch is difficult to meet the increasing application requirements. In this paper, a parallel topology terahertz meta-chip switch based on the combination of equivalent circuit theory and electromagnetic coupling is proposed. The meta-chip is realized by adjusting the density of two-dimensional electron gas of InP-HEMT, which converts the electromagnetic coupling between the microstructure and microstrips. By using the 90 nm gate length InP-HEMT process, a C-ring loaded meta-chip is fabricated and tested in this paper. The results show an insertion loss lower than 1 dB with a 10 dB switching ratio, which is 20% higher than that without C-ring while ensuring the rather low insertion loss. It shows that the presented mechanism has positive significance for the design of terahertz band functional devices.