Flexible Visible-Infrared Metamaterials and Their Applications in Highly Sensitive Chemical and Biological Sensing

Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371.
Nano Letters (Impact Factor: 13.59). 06/2011; 11(8):3232-8. DOI: 10.1021/nl2014982
Source: PubMed


Flexible electronic and photonic devices have been demonstrated in the past decade, with significant promise in low-cost, light-weighted, transparent, biocompatible, and portable devices for a wide range of applications. Herein, we demonstrate a flexible metamaterial (Metaflex)-based photonic device operating in the visible-IR regime, which shows potential applications in high sensitivity strain, biological and chemical sensing. The metamaterial structure, consisting of split ring resonators (SRRs) of 30 nm thick Au or Ag, has been fabricated on poly(ethylene naphthalate) substrates with the least line width of ∼30 nm by electron beam lithography. The absorption resonances can be tuned from middle IR to visible range. The Ag U-shaped SRRs metamaterials exhibit an electric resonance of ∼542 nm and a magnetic resonance of ∼756 nm. Both the electric and magnetic resonance modes show highly sensitive responses to out-of-plane bending strain, surrounding dielectric media, and surface chemical environment. Due to the electric and magnetic field coupling, the magnetic response gives a sensitivity as high as 436 nm/RIU. Our Metaflex devices show superior responses with a shift of magnetic resonance of 4.5 nm/nM for nonspecific bovine serum albumin protein binding and 65 nm for a self-assembled monolayer of 2-naphthalenethiol, respectively, suggesting considerable promise in flexible and transparent photonic devices for chemical and biological sensing.

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    • "Flexible photonic crystals123456789101112131415 based on soft matters like polymers with response in different spectral bands may be applied extensively in optoelectronic devices, sensors, and tunable optical filters16. When active materials like polymeric semiconductors are incorporated into flexible photonic crystals, lasers or light-emitting devices with large tuning dynamics may be achieved1718. "
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    ABSTRACT: Flexible photonic crystals are attractive devices owing to their multifold tunable parameters additionally introduced by soft substrates or by nanostructured, nano-doped, or nano-embedded soft matters. This not only extends significantly the intrinsic functions of photonic crystals, but also facilitates easy integration of the photonic crystal device into various optoelectronic and sensing systems. So far, flexible metallic photonic structures have been constructed on micrometer scales with complex fabrication procedures. Much simpler and more reproducible methods are expected to achieve such metamaterials in large scales and at low costs. In address to these challenges, we developed a straightforward approach to create soft plasmonic photonic crystals consisting of gold nanolines arranged on stretchable substrates with nanoscale periods, centimeter-scale areas, and high reproducibility using annealed gold nanoparticle colloids.
    Scientific Reports 02/2014; 4:4182. DOI:10.1038/srep04182 · 5.58 Impact Factor
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    • "Gu et al. [102] reported a magnetic plasmonic metamaterial which was constructed with a metal ring-shaped disk array supported by a dielectric layer on a metal film for high sensitive refractive index sensing. Xu et al. [103] reported a flexible metamaterial (Metaflex)-based photonic device operating in the visible-IR regime, which showed potential applications in high sensitivity strain, biological and chemical sensing. "
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    ABSTRACT: Metamaterials are artificial media structured on a size scale smaller than wavelength of external stimuli, and they can exhibit a strong localization and enhancement of fields, which may provide novel tools to significantly enhance the sensitivity and resolution of sensors, and open new degrees of freedom in sensing design aspect. This paper mainly presents the recent progress concerning metamaterials-based sensing, and detailedly reviews the principle, detecting process and sensitivity of three distinct types of sensors based on metamaterials, as well as their challenges and prospects. Moreover, the design guidelines for each sensor and its performance are compared and summarized.
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