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We report the successful growth of vanadium dioxide (VO 2 ) films on SiO 2 buffered metal electrode and the fabrication of metal–oxide-insulator–metal (MOIM) junction. The VO 2 film has an abrupt thermal-induced metal–insulator transition (MIT) with a change of resistance of 2 orders of magnitude. The electrically-driven MIT (E-MIT) switching characteristics have been investigated by applying perpendicular voltage to VO 2 based MOIM device at particular temperatures, sharp jumps in electric current were observed in the I – V characteristics under a low threshold voltage of 1.6 V. The Ohmic behavior, non-Ohmic super-linear one, and metallic regime are sequentially observed in the MOIM device with the increase of voltage. It is expected to be of significance in exploring ultrafast electronic devices incorporating correlated oxides based MOIM structure.

We present a tunable reflector based on VO2 thin films in the terahertz frequency range. The reflectance of the reflector in the terahertz region can be tuned by controlling electrical properties of VO2 thin films. The change of electrical properties of VO2 originates from an insulator-metal transition of VO2. The experimental results demonstrated the effectiveness of the tunable reflector in the terahertz region. The tunable reflector of the VO2 thin films is very suitable for terahertz systems.

We report the growth of vanadium dioxide (VO2) films on metal electrode with a thin SiO2 buffer and the fabrication of nanoscale metal-oxide-metal junction. The thermal-induced metal-insulator transition with a change of resistance of 2 orders of magnitude is observed and the threshold voltage is as low as 1.6V.

High quality VO2 thin films were fabricated on BK7 substrate. A distinct semiconductor-metal phase transition was obtained, accompanying by a resistivity change of 4 orders of magnitude and a terahertz transmission modulation about 89%.

We design and experimentally demonstrate a broadband metamaterial absorber in the terahertz (THz) band based on a periodic array of aluminum (Al) squares with two different sizes. A thin silicon dioxide (SiO2) film rather than a conventional polyimide (PI) layer is used as a dielectric spacer to separate Al squares from the platinum (Pt) ground plane in our design, which significantly improves the design precision and the feasibility of the device fabrication. The combination of different sizes of Al squares gives rise to an absorption bandwidth of over 210 GHz with an absorption of over 90%. Our results also show that our device is almost polarization-insensitive. It works very well for all azimuthal angles with an absorption of beyond 80%.