A semi‐analytical theoretical model is presented, which describes the operation of a selective molecular sensor employing a double resonance between a dipole‐active molecular vibration mode, tunable surface plasmons in a periodic structure of graphene nanoribbons (NRs), and the incident light, in the THz‐to‐IR range, used for testing. The model is based on the solution of Maxwell's equations for the NR structure deposited on a dielectric substrate, using the electromagnetic Green's function, and is extended to the case of an additional (buffer) layer present between the NRs and the substrate. Both the graphene NRs and the layer of adsorbed molecules are considered as 2D, since their thicknesses are very small in comparison with the wavelength of the incident light. The model is applied to different molecular systems, the protein studied by Rodrigo et al. [Science 2015, 349, 165], for which an excellent agreement with experimental data is obtained, and an organometallic molecule Cd(CH3)2. Two different assumptions concerning the way of sticking of the analyte molecules to the sensor's surface are considered and the limitations of these sensing principles are discussed.

Optical Tamm states (OTS) are confined optical modes that can occur at the interface between two highly reflective structures. However, due to the strong reflectance required, their implementation with highly processable and metal-free flexible materials has proven challenging. Herein, we develop the first structure supporting OTS based only on organic polymeric materials, demonstrating a photonic platform based on non-critical, widely available and easily processable materials. The structures fabricated present large areas and consist of a narrowband multi-layered polymeric distributed Bragg reflector (DBR) followed by a thin film of J-aggregate molecular excitonic material that can act as a highly reflective surface within a narrowband range. We take advantage of the narrowband spectral response of the DBR and of the reflective molecular layer to tune the OTS band by varying the periodicity of the multilayer, opening the door for the fabrication of OTS structures based on lightweight integrable excitonic devices with cost-effective procedures.

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In article number http://doi.wiley.com/10.1002/pssb.202200055, André Souto, Diogo Cunha, and Mikhail I. Vasilevskiy present a semi‐analytical theoretical model which describes the operation of a selective molecular sensor employing a double resonance between a dipole‐active molecular vibration, electrically tunable surface plasmons in a periodic structure of graphene nanoribbons, and the incident light in the terahertz‐to‐infrared range. The model is based on the solution of Maxwell’s equations for the nanoribbon structure deposited on a dielectric substrate with an additional dielectric layer between the bottom gate and the nanoribbons. The thickness of this layer can be adjusted in order to enhance, via constructive interference, the plasmonic resonance (see figure) and, consequently, the sensing platform–analyte coupling. – This article belongs to the Special Section “Mathematical Modelling in Materials Science of Electronic Components” (see Guest Editorial by Nikolai A. Sobolev and Karine K. Abgaryan, article number http://doi.wiley.com/10.1002/pssb.202200505).