16:30 〜 16:45
▼ [24p-E303-12] An electromechanically active THz filter based on an H-shaped metamaterial
キーワード：Metamaterials, THz waves, MEMS
I. Introduction
Terahertz (THz) waves (0.1–10 THz in frequency) have many potential applications owing to their spectral specificity. To further develop THz wave technology, active filters that dynamically manipulate the transmission of waves are researched by using reconfigurable metamaterial (MM). In this study, a tunable THz filter integrating an H-shaped MM (H-MM) with micro-electro-mechanical systems (MEMS) ohmic switches is proposed and calculated their characteristics. The shape of the H-MM is mechanically changed by MEMS actuators. Thus, the transmittance of the filter is controllable.
II. Design
A quartz substrate is used. Leads that provide drive voltage are embedded under a 0.13-µm-thick SiO2; an H-shaped 2D gold MM is formed on the surface layer, it consists of two arms and a split-bar; the MEMS actuator array is composited of suspended cantilevers. The MEMS actuator array is arranged upon the split-bar of the H-MM. By applying a potential between leads and the H-MM, the suspended tip of the cantilever will pull down to touch the H-MM then switches the device from the off (δ = 0.3 μm) to on (δ = 0 μm) state.
III. Optical characteristics
At the on state (δ = 0 μm), the filter presents a broad valley with a central frequency of 0.65 THz and a minimum of −29 dB in the transmittance spectrum. When the cantilever is released without the actuation potential (off state, δ = 0.3 μm), it works in an LC resonant mode, which disappears the dip in transmittance at the frequency of 0.65 THz. Moreover, a vertical 50-nm-displacement of the cantilever tip can switch the on-to-off states of the filter.
IV. Conclusions
An active THz filter was proposed by integrating an H-shaped MM and a MEMS actuator array. The filter presents a 70%-change in transmittance at a frequency of 0.65 THz.
Terahertz (THz) waves (0.1–10 THz in frequency) have many potential applications owing to their spectral specificity. To further develop THz wave technology, active filters that dynamically manipulate the transmission of waves are researched by using reconfigurable metamaterial (MM). In this study, a tunable THz filter integrating an H-shaped MM (H-MM) with micro-electro-mechanical systems (MEMS) ohmic switches is proposed and calculated their characteristics. The shape of the H-MM is mechanically changed by MEMS actuators. Thus, the transmittance of the filter is controllable.
II. Design
A quartz substrate is used. Leads that provide drive voltage are embedded under a 0.13-µm-thick SiO2; an H-shaped 2D gold MM is formed on the surface layer, it consists of two arms and a split-bar; the MEMS actuator array is composited of suspended cantilevers. The MEMS actuator array is arranged upon the split-bar of the H-MM. By applying a potential between leads and the H-MM, the suspended tip of the cantilever will pull down to touch the H-MM then switches the device from the off (δ = 0.3 μm) to on (δ = 0 μm) state.
III. Optical characteristics
At the on state (δ = 0 μm), the filter presents a broad valley with a central frequency of 0.65 THz and a minimum of −29 dB in the transmittance spectrum. When the cantilever is released without the actuation potential (off state, δ = 0.3 μm), it works in an LC resonant mode, which disappears the dip in transmittance at the frequency of 0.65 THz. Moreover, a vertical 50-nm-displacement of the cantilever tip can switch the on-to-off states of the filter.
IV. Conclusions
An active THz filter was proposed by integrating an H-shaped MM and a MEMS actuator array. The filter presents a 70%-change in transmittance at a frequency of 0.65 THz.