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The design and fabrication of a novel plasmonic cavity, intended to allow far-field recovery of signals arising from near field magneto-optical interactions, is presented. Finite element modeling is used to describe the interaction between a gold film, containing cross-shaped cavities, with a nearby magnetic under-layer. The modeling revealed strong electric field confinement near the center of the cross structure for certain optical wavelengths, which may be tuned by varying the length of the cross through a range that is compatible with available fabrication techniques. Furthermore, the magneto optical Kerr effect (MOKE) response of the composite structure can be enhanced with respect to that of the bare magnetic film. To confirm these findings, cavities were milled within gold films deposited upon a soluble film, allowing relocation to a ferromagnetic film using a float transfer technique. Cross cavity arrays were fabricated and characterized by optical transmission spectroscopy prior to floating, revealing resonances at optical wavelengths in good agreement with the finite element modeling. Following transfer to the magnetic film, circular test apertures within the gold film yielded clear magneto-optical signals even for diameters within the sub-wavelength regime. However, no magneto-optical signal was observed for the cross cavity arrays, since the FIB milling process was found to produce nanotube structures within the soluble under-layer that adhered to the gold. Further optimization of the fabrication process should allow recovery of magneto-optical signal from cross cavity structures. [ABSTRACT FROM AUTHOR]

We show that the transmission of light through metallic hole arrays supported by a glass substrate can be tuned by depositing a controlled number of Langmuir–Blodgett layers on top of the hole array. Enhanced transmission is achieved when the number of overlayers is such that the surface plasmon-polariton modes on the two sides of the metal hole array have matched wavevectors. Dye molecules introduced into some of these overlayers allow us to explore the relationship between molecular fluorescence and the transmission properties of the structure, through measurement of the fluorescence lifetime of the molecules. We find there to be little change in the fluorescence lifetime between enhanced and non-enhanced transmission regimes and offer an explanation of our findings in terms of changes in the photonic mode density. [ABSTRACT FROM AUTHOR]

We present experimental results showing the variation in photoluminescence from an organic material emitted through a thin metal film as successive dielectric overlayers are added to the far side of the metal. The intensity of the emission from the structure is examined as the surface plasmon–polariton (SPP) modes associated with the two metal surfaces evolve with increasing overlayer thickness from individual to coupled SPP modes. The SPP modes are scattered to produce light by the addition to the metal film of wavelength-scale periodic microstructure. We show that the addition of a dielectric overlayer of an appropriate thickness to the metal film is accompanied by an increase in the intensity of the emission by a factor of 3 over a similar structure with no dielectric overlayer, and by a factor of 50 over a similar planar structure. We show that this increase in emission is mediated via coupled SPP modes. [ABSTRACT FROM AUTHOR]

The paper reports measurements on the efficiency of coupling between a surface plasmon polariton mode and radiation using a periodic corrugated surface. For surface plasmon polaritons (SPPs) propagating parallel to the Bragg vector of the corrugation, coupling efficiencies of 70% were observed. The coupling efficiency was also measured for different SPP propagation directions relative to the corrugation and found to be high over a wide range of SPP propagation directions. These results are discussed in the context of emission from SPP-based light emitting devices. [ABSTRACT FROM AUTHOR]

By employing a combination of time-domain measurements and numerical calculations, we demonstrate that the semiconductor InSb supports a strongly confined surface plasmon (SP) in the terahertz frequency range. We show that these SPs can be used to enhance the light-matter interaction with dielectric layers above the semiconductor surface, thereby allowing us to detect the presence of polystyrene layers around 1000 times thinner than the free space wavelength of the terahertz light. Finally we discuss the viability of using semiconductor SPs for the purposes of terahertz sensing and spectroscopy. [ABSTRACT FROM AUTHOR]

We present experimental results showing electroluminescence from a dendrimer based organic light-emitting diode (OLED) mediated via surface plasmon polariton (SPP) modes. A combination of angle dependent electroluminescence, photoluminescence, and reflectance measurements is used to identify emission originating from the guided modes of the device. It is found that the SPP modes, which are usually nonradiative, are coupled to light by a wavelength scale periodic microstructure. It is demonstrated that the necessary microstructure can be readily fabricated by solvent-assisted micromoulding. Our results indicate that such an approach may offer a means to increase the efficiency of dendrimer based OLEDs. [ABSTRACT FROM AUTHOR]

We show that the emission of light from a dye layer through an adjacent thin silver film is maximal for a silver thickness of approximately 50 nm. This effect is explained as the result of competition between enhancement of the electric field at the metal surface due to the excitation of a surface plasmon-polariton mode, the amount of power coupled to the surface plasmon-polariton mode, and the attenuation of the field transmitted through the silver, all three of which vary with metal thickness. We indicate how these findings may be of relevance in the design of some surface plasmon-polariton-based fluorescence biosensing schemes. [ABSTRACT FROM AUTHOR]

We report strong photoluminescence from a top-emitting organic light-emitting structure where emission takes place through a thin (55 nm) silver film. We show that this emission is mediated via coupled surface plasmon-polariton modes. Our results show that the addition of a dielectric grating to otherwise planar structures, such as surface-emitting organic light-emitting diodes, may offer a way to increase the external efficiency of top-emitting organic light-emitting diodes. [ABSTRACT FROM AUTHOR]