Terahertz phase shifter based the fin-line loaded with microstructures nested with VO2

This paper presents a structure of terahertz phase shifter based the fin-line loaded with microstructures nested with VO2. In this structure, the fin-line is used to transmit terahertz waves, and four phase-shifting units nested with VO2 are designed on the back of the substrate. With the phase transition characteristic of VO2 changed by the pump laser, the on-off state of four phase-shifting units can be well controlled. Finally, within 335GHz-345GHz, the losses of phase-shifting units are less than 2dB, a phase shift of 171.6 degrees can be achieved at 340 GHz, and each phase-shifting unit has a nearly 45 degrees phase shift.