title: Microelectromechanically tunable multiband metamaterial with preserved isotropy.
abstract: We experimentally demonstrate a micromachined reconfigurable metamaterial with polarization independent characteristics for multiple resonances in terahertz spectral region. The metamaterial unit cell consists of eight out-of-plane deformable microcantilevers placed at each corner of an octagon ring. The octagon shaped unit cell geometry provides the desired rotational symmetry, while the out-of-plane movable cantilevers preserves the symmetry at different configurations of the metamaterial. The metamaterial is shown to provide polarization independent response for both electrical inductive-capacitive (eLC) resonance and dipolar resonance at all states of actuation. The proposed metamaterial has a switching range of 0.16 THz and 0.37 THz and a transmission intensity change of more than 0.2 and 0.7 for the eLC and dipolar resonances, respectively for both TE and TM modes. Further optimization of the metal layer thickness, provides an improvement of up to 80% modulation at 0.57 THz. The simultaneously tunable dual band isotropic metamaterial will enable the realization of high performance electro-optic devices that would facilitate numerous terahertz applications such as compressive terahertz imaging, miniaturized terahertz spectroscopy and next generation high speed wireless communication possible in the near future.
authors.affiliation: 1] Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117576 [2] Center for Intelligent Sensors and MEMS, National University of Singapore, 4 Engineering Drive 3, Singapore 117576 [3] Institute of Microelectronics, A*STAR (Agency for Science, Technology and Research), 11 Science Park Road, Singapore Science Park II, Singapore 117685. [4] NUS Suzhou Research Institute (NUSRI), Suzhou Industrial Park, Suzhou, P. R. China 215123.
authors.forename: Prakash
authors.initials: P
authors.lastname: Pitchappa
authors.affiliation: 1] Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117576 [2] Center for Intelligent Sensors and MEMS, National University of Singapore, 4 Engineering Drive 3, Singapore 117576 [3] Institute of Microelectronics, A*STAR (Agency for Science, Technology and Research), 11 Science Park Road, Singapore Science Park II, Singapore 117685. [4] NUS Suzhou Research Institute (NUSRI), Suzhou Industrial Park, Suzhou, P. R. China 215123.
authors.forename: Chong Pei
authors.initials: CP
authors.lastname: Ho
authors.affiliation: 1] Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117576 [2] Center for Intelligent Sensors and MEMS, National University of Singapore, 4 Engineering Drive 3, Singapore 117576 [3] NUS Suzhou Research Institute (NUSRI), Suzhou Industrial Park, Suzhou, P. R. China 215123.
authors.forename: You
authors.initials: Y
authors.lastname: Qian
authors.affiliation: 1] Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117576 [2] Center for Intelligent Sensors and MEMS, National University of Singapore, 4 Engineering Drive 3, Singapore 117576 [3] NUS Suzhou Research Institute (NUSRI), Suzhou Industrial Park, Suzhou, P. R. China 215123.
authors.forename: Lokesh
authors.initials: L
authors.lastname: Dhakar
authors.affiliation: Institute of Microelectronics, A*STAR (Agency for Science, Technology and Research), 11 Science Park Road, Singapore Science Park II, Singapore 117685.
authors.forename: Navab
authors.initials: N
authors.lastname: Singh
authors.affiliation: 1] Department of Electrical and Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117576 [2] Center for Intelligent Sensors and MEMS, National University of Singapore, 4 Engineering Drive 3, Singapore 117576 [3] NUS Suzhou Research Institute (NUSRI), Suzhou Industrial Park, Suzhou, P. R. China 215123.
authors.forename: Chengkuo
authors.initials: C
authors.lastname: Lee