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The transverse magnetic (TM) polarized hybrid modes formed as a consequence of coupling between Tamm plasmon polariton (TM-TPP) mode and surface plasmon polariton (SPP) mode exhibit interesting dispersive features for realizing a highly sensitive and accurate surface plasmon resonance (SPR) sensor. We found that the TM-TPP modes, formed at the interface of distributed Bragg reflector and metal, are strongly dispersive as compared to SPP modes at optical frequencies. This causes an appreciably narrow interaction bandwidth between TM-TPP and SPP modes, which leads to highly accurate sensing. In addition, appropriate tailoring of dispersion characteristics of TM-TPP as well as SPP modes could ensure high sensitivity of a novel SPR platform. By suitably designing the Au/TiO₂/SiO₂-based geometry, we propose a TM-TPP/SPP hybrid-mode sensor and achieve a sensitivity ≥900  nm/RIU with high detection accuracy (≥30  μm⁻¹) for analyte refractive indices varying between 1.330 and 1.345 in 600-700 nm wavelength range. The possibility to achieve desired dispersive behavior in any spectral band makes the sensing configuration an extremely attractive candidate to design sensors depending on the availability of optical sources.

The objective of the proposed work is to design a biosensor that monitors hemoglobin (Hb) concentration using the combination of nanolayer, i.e., barium titanate (BaTiO3) and antimonene based on surface plasmon resonance (SPR) technique. Antimonene is used here as bio-recognition element (BRE) layer to attach the Hb analyte through physical adsorption due to its hydrophilic nature, higher adsorption energy and larger active surface area. The use of BaTiO3 adlayer (7 nm) just before antimonene is to enhance the refractive index (RI) sensitivity up to 1.90 times for the proposed SPR biosensor. The reason behind sensitivity enhancement is its high dielectric constant which enhances the electromagnetic field with in analyte medium. The performance of the biosensor is demonstrated with performance parameters namely sensitivity, detection accuracy (DA), figure of merit (FOM) and resolution. The proposed biosensor has potential to achieve much higher performance in terms of RI sensitivity of 303.83°/RIU, FOM of 50.39 RIU−1 and resolution of 0.021 g/l in comparison with reported biosensors in the literature for detection of Hb concentration. Thus, based on the obtained results one can say that the proposed work unlocks a reliable sensing in the field of medical science to detect hemoglobin-related diseases in human being. [ABSTRACT FROM AUTHOR]

In this study, we analyze the combined effect of TMD/Perovskite/2D Material on the performance of SPR biosensor using Kretschman configuration. In order to optimize the parameters, we compare the results of each material falls in the family of TMD/Perovskite/2D respectively and finally applied in the proposed sensor. It is observed that the combined structure based on black phosphorus, a 2D material, Barium Titanate (BaTiO3) as a Perovskite material and Tungsten disulfide (WS2) as a TMD material respectively shows excellent performance in terms of a performance parameter of the sensor. Incident light wavelength is fixed of 633 nm and radiative properties of a multi‐layered structure are calculated by transfer Metrix method. Essential performance parameters like Figure of Merit (FOM), Sensitivity, Detection Accuracy obtained by using the standard formula given in the paper. The reported figure of merit (FoM) and sensitivity are 62.51/RIU and 370. respectively. The results obtained in this paper expect to prove a significant role in the biosensing field like DNA hybridization as well as for the application of Perovskite materials in biosensing. [ABSTRACT FROM AUTHOR]

Hybrid modes formed as a consequence of coupling between Tamm-plasmon polariton (TPP) mode and surface plasmon polariton (SPP) mode in a metallo-dielectric heterostructure geometry exhibit interesting dispersive features which can be employed for realizing highly sensitive and accurate surface-plasmon-resonance (SPR) sensor. The transverse magnetically (TM) polarized TPP modes (TM-TPP), formed at the interface of distributed-Bragg reflector (DBR) and metal, are strongly dispersive as compared to SPP modes at optical frequencies that forms the basis of narrow interaction bandwidth which, in turn, results in improved accuracy of sensing. By deploying a nano/micro-fabrication compatible TiO 2 /SiO 2 -based DBR architecture in combination with different plasmon-active metals such as gold (Au), silver (Ag) and aluminum (Al), we propose a TM-TPP and SPP hybrid-mode sensor which exhibit high sensitivity ≥ 900 nm/RIU for analyte refractive indices varying between 1.330 and 1.345. The investigation also revealed that the hybrid-mode sensor is most accurate in case of Al-based configuration amongst Au, Ag and Al which is primarily due to weaker dispersion characteristics exhibited by Al at visible frequencies. Since, the dispersive behavior of TM-TPP modes could be tailored appropriately in any spectral band, the sensing configuration could be immensely useful for designing sensors at those wavelength where optical sources are readily available. [ABSTRACT FROM AUTHOR]

Abstract: A highly sensitive surface plasmon resonance (SPR) sensor based on channel photonic crystal waveguide (PCW) is proposed. The PCW is based on widely used lithographic and nano-fabrication compatible materials like TiO2 and SiO2. Gold has been used as a SPR active metal. By rigorously optimizing the different waveguide parameters, we have shown that there is significant transfer of modal power around phase-matching or resonance wavelength which has been utilized to design a compact and highly sensitive sensor for lab on chip. The ultra narrow width (∼765pm for an interaction length of 10mm) of surface plasmon resonance curve and sensitivity as high as 7500nm-RIU−1 will open a new window for bio-chemical sensing applications. [Copyright &y& Elsevier]

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]

• An SPR sensor proposed using Ti 3 C 2 T x MXene nanomaterial. • High sensitivity 190.22 (°/ RIU) is obtained using a single layer of Ti 3 C 2 T x MXene. • The penetration depth of the sensor is 1.52 times larger compared to a conventional sensor. The aim of the paper is to see the effect of new nanomaterial, i.e., MXene on sensing application. A surface plasmon resonance biosensor comprising of BK7 prism, MXene, transition metal dichalcogenides (TMDCs), black phosphorus (BP), and gold (Au) as a plasmonic material is proposed for sensing application in visible region. We have investigated and carried out detailed analysis to design the high-performance biosensor by exploiting the unique properties of Ti 3 C 2 T x MXene and black phosphorus. The performance of the biosensor is quantified in terms of sensitivity. The highest sensitivity 190.22 (° / R I U) is obtained using single layer of each nanomaterials. Proposed sensor offered penetration depth i.e., 1.52 times larger in compared to conventional sensor. Our contribution reveals potential application of combination of Black Phosphorus, Ti 3 C 2 T x MXene and TMDCs as a new type of biosensor providing promising applications in SPR biosensors. [ABSTRACT FROM AUTHOR]