Active MEMS metamaterials for THz bandwidth control
Ho, Chong Pei
Date of Issue2017
School of Physical and Mathematical Sciences
We experimentally demonstrate a microelectromechanical system (MEMS) based metamaterial with actively tunable resonance bandwidth characteristics, operating in the terahertz (THz) spectral region. The broadband resonance characteristic feature of the MEMS metamaterial is achieved by integrating sixteen microcantilever resonators of identical lengths but with continuously varying release lengths, to form a supercell. The MEMS metamaterial showed broadband resonance characteristics with a full width half maximum (FWHM) value of 175 GHz for resonators with a metal thickness of 900 nm and was further improved to 225 GHz by reducing the metal thickness to 500 nm. The FWHM resonance bandwidth of the MEMS metamaterial was actively switched to 90 GHz by electrostatically controlling the out-of-plane release height of the constituent microcantilever resonators. Furthermore, the electrically controlled resonance bandwidth allows for the active phase engineering with relatively constant intensity at a given frequency based on the reconfiguration state of the MEMS metamaterial. This enables a pathway for the realization of actively controlled transmission or reflection based on dynamically programmable THz metamaterials.
Applied Physics Letters
© 2017 AIP Publishing. This paper was published in Applied Physics Letters and is made available as an electronic reprint (preprint) with permission of AIP Publishing. The published version is available at: [http://dx.doi.org/10.1063/1.4980115]. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper is prohibited and is subject to penalties under law.