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We propose a hybrid Tamm-plasmon-polariton (TPP) mode based sensing scheme for accurate determination of temperature. The sensing architecture is comprised of dual “metal-distributed-Bragg-reflector (DBR)” based structure, which sandwiches a common layer acting as a temperature sensing medium. Hybrid-TPP modes formed as a consequence of individual TPP mode-coupling is characterized by two distinct sharp reflectivity minima within the photonic bandgap of DBR for normal incidence of broadband source. The symmetric hybrid mode exhibits discernible variation in terms of change in reflectivity and resonance wavelength as the temperature of the sensing layer alters. On the other hand, the antisymmetric mode remains unchanged that gives rise to self-referenced temperature sensing scheme. We obtained a spectral sensitivity of 50 pm/°C by optimally choosing the thickness of sensing layer. In addition, the sharp TPP resonances gives rise to improved detection accuracy of such a sensing configuration as compared to competing optical sensing technologies. [ABSTRACT FROM PUBLISHER]

We propose a high-performance bimetallic surface plasmon resonance (SPR) sensor based on periodic-multilayer waveguide and analyze its performance with respect to SPR active metals, such as gold (Au) and aluminum (Al). We found that an ultra thin (\sim3 nm) layer of gold (Au) over aluminum (Al) protects aluminum (Al) from oxidation and exhibits better sensor performance. Using couple-mode theory, we show that the sensitivity and detection accuracy could be appropriately tailored for bimetallic (Au+Al) configuration. [ABSTRACT FROM PUBLISHER]

A self-referenced sensor based on coupled hybrid mode Tamm-plasmon-polariton (TPP) is proposed for detection of different blood group components. The geometry which has been investigated theoretically, is comprised of blood components sandwiched between two ‘metal-distributed Bragg reflectors (DBRs)’ exhibiting two distinguishable absorption peaks within the photonic band-gap (PBG) of DBR. The two absorption maxima are essentially due to excitation of one symmetric (Mode-I) and one anti-symmetric mode (Mode-II) within the PBG. Mode-I remains invariant for a change of blood constituents whereas Mode-II exhibits strong dispersive properties by virtue of significant presence within the sensing region. This gives rise to a hybrid self-reference scheme where the longer wavelength arm (Mode-II) varies significantly providing proper signature of a particular blood component. A straight line fit to the resonance wavelength shift gives rise to a sensitivity of ≈200 nm/RIU with the proposed architecture. The polarization dependence of the spectral shift of hybrid-mode resonance wavelengths for oblique incidence is also investigated and analyzed theoretically. The sharp absorption maxima facilitate precise detection with an improved detection accuracy of a particular blood component. A brief analysis to optimize the sensor design for enhanced sensitivity, as well as detection accuracy, has also been discussed. [ABSTRACT FROM AUTHOR]

We demonstrate a Tamm-plasmon-polariton (TPP) based sensor for accurate determination of temperature. The sensing architecture is comprised of thin silver (Ag) film on a distributed-Bragg-reflector (DBR) structure made of periodically stratified multilayers of Ta 2 O 5 and SiO 2 . TPP mode is excited using direct incidence of white-light-source at normal incidence as well as oblique incidence. The mode excitation is characterized by a sharp reflectivity minimum within the photonic bandgap (PBG) of DBR. It was observed that the depth of TPP resonance reduces uniformly as a function of temperature without affecting its sharpness. Defining temperature sensitivity in terms of change in reflectivity from the composite structure, a sensitivity of 7.8 × 10 −4 /°C is estimated for the sensing geometry. Also, the metallo-dielectric geometry supporting TPP modes is modeled using transfer-matrix-method for ascertaining the salient features of TPP modes which have a direct impact on sensing properties. [ABSTRACT FROM AUTHOR]