LAUSR

We propose a wide band terahertz (THz) switch of undulated waveguide with vanadium dioxide (VO2 ) film coated inner wall. The forbidden bands formed by periodically undulated walls effectively restrain THz transmission when VO2 is in the insulator phase. An unexpected wide band appears in the transmission spectrum, connecting two forbidden bands, where metal phase VO2 covers the undulations and eliminates band gaps. Simulations confirm that the switch could be realized by varying the temperature in the frequency range 0.71–1.07 THz, and hence such a switch could be applied in THz systems.