Electromechanically Rotatable Cross-Shaped Mid-IR Metamaterial

• Main Authors: Jitong Zhong, Yu-Sheng Lin
• Format: Article
• Language: English
• Published: MDPI AG 2020-05-01
• Series: Crystals
• Subjects: electromechanically; rotatability; metamaterials; multi-functionalities; IR filter
• Online Access: https://www.mdpi.com/2073-4352/10/6/431

We present an electromechanically rotatable infrared (IR) cross-shaped metamaterial (CSM) in the mid-IR wavelength range. The CSM configuration is composed of double gold layers with cross-shaped nanostructures. To investigate the fano-resonance within CSM nanostructures, the aspect ratios and length ratios of CSM are compared and discussed. The electromagnetic responses exhibit the characteristics of large tuning range, tunable broad and narrow bandwidths. By properly tailoring the aspect ratio of CSM, the resonance can be tuned with bidirectional tuning in the range of 650 nm. CSM with different length ratios exhibit narrowband resonances around the wavelength of 4.6 μm and broadband resonances in the wavelength range of 5.0 μm to 6.5 μm. These characteristics of CSM with different aspect ratios and length ratios could be potentially used in IR narrowband and broadband filter. To further increase the flexibility of proposed electromechanically rotatable CSM, an actively tunable narrowband and broadband filter in the mid-IR wavelength range is performed. This study provides a unique approach to realizing an IR filter, with high flexibility.