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Carbon allotropes-based nanomaterials possess unique physical and chemical properties including high surface area, the possibility of pi-stacking interaction with a wide range of biological objects, rich availability of oxygen-containing functional groups in graphene-oxide (GO), and excellent optical properties, which make them an ideal candidate for use as a universal immobilization platform in SPR biosensing. Here, we propose a new surface plasmon resonance (SPR) biosensing interface for sensitive and selective detection of small molecules. This interface is based on the GO linking layers deposited on the gold/copper surface of SPR sensor chips. To estimate the binding capacity of GO layers, modification of carboxyl groups to N-Hydroxysuccinimide esters was performed in the flow cell of SPR instrument. For comparison, the same procedure was applied to commercial sensor chips based on linking layers of carboxymethylated dextran.

The performance of metal-based devices is limited by ohmic losses in the metal, which are determined by electron scattering. The structural properties of gold thin films also play an important role in the film quality, which may affect its' optical properties and the overall capability of the device. At the same time, metal films of different thicknesses are needed for different applications and, since these films are polycrystalline, their internal properties and surface roughness can greatly vary from one thickness to another. In this work, we study, using atomic force microscopy and spectroscopic ellipsometry, the structural morphology and optical properties of polycrystalline gold thin films (fabricated by e-beam deposition at a low sputtering rate smooth gold) in the thickness range of 20 - 200 nm. By extracting the real and imaginary dielectric function and the Drude parameter of electron relaxation rate we demonstrate that the optical losses increase mainly when the film thickness gets lower than 66 nm. Our results reveal that the thickness-dependent contribution is inversely proportional to the film thickness. The experimental results are confirmed by the theoretical model, which predicts optical losses based on structure of the gold films.

We propose a novel scheme of surface plasmon polariton (SPP) amplification by stimulated emission of radiation. It is based on a minority carrier injection in an Au/InAs Schottky diode. The proposed amplifier is electrically pumped and has a planar structure. Therefore, it is very compact and can be coupled easily to plasmonic waveguides.

We propose a novel scheme of the semiconductor surface plasmon amplifier. It is based on a minority carrier injection in a metal‐insulator‐semiconductor diode. The principle of operation is as follows. Excess electrons and holes recombine radiatively and emit photons. If the difference between quasi‐Fermi levels exceeds the bandgap, the surface plasmon plasmon polariton (SPP) is amplified. A compact size and a planar structure of the amplifier allow to utilize it in integrated optical circuits and couple it easily to passive plasmonic devices. Moreover, the proposed technique can be used to obtain sufrace plasmon lasing by analogy with semiconductor lasers.

We propose a novel scheme of the plasmonic cavity. It is based on insulator‐metal‐insulator (IMI) waveguide of finite length. Surface plasmon polaritons (SPPs) guided by IMI structure can exhibit extremely small energy velocity and thus the losses are determined mainly by the properties of the material used rather than the geometry of the cavity. Accordingly, we should care only about the metal film thicknesses and the purity of the metal and may not take into account the length of the cavity that simplifies the fabrication process. Moreover, it is possible to design nanocavity with all dimensions less than the wavelength of light. Using analytical and numerical techniques (FDTD method), we obtain the quality factor and other parameters of such cavities.