Plasmon coupling

In photoexcited polar semiconductors, the coherent LO phonons couple with photocarriers to form coherent LO phonon-plasmon coupled (LOPC) modes, which exhibit fundamentally different properties from those of bare phonons. Huber and coworkers revealed the ultrafast transition of an optical... 

Gryczynski I, Malicka J, Jiang W, Fischer H, Chan WCW, Gryczynski Z, Grudzinski W, Lakowicz JR (2005) Surface-plasmon-coupled emission of quantum dots. J Phys Chem B 109 1088-1093... 

C. F. Eagen, W. H. Weber, S. L. McCarthy, and R. W. Terhune, Time dependent decay of surface plasmon-coupled molecular fluorescence, Chem. Phys. Lett. 75, 274 277 (1980). 

This strong plasmon absorption and its sensitivity to the local environment have made Au NPs and nanomaterials attractive candidates as colorimetric sensors. Colorimetric response can be due to the metal particle aggregation, which affects the SPR band of the isolated particles due to plasmon coupling and induced dipoles. 

FIGURE 1 Phonon, plasmon and phonon-plasmon coupled modes in Raman and infrared reflection spectroscopy as a function of free electron density (+ data from [25], see also [3]) [24],... 

Infrared absorption in typically highly n-type bulk GaN is mainly controlled by free carrier absorption [37,38], Infrared reflection of phonons and phonon-plasmon coupled modes in GaN in the range of the reststrahl band has been reported [1,8,9,37], Similarly to the interpretation of coupled modes in Raman... 

The first investigation of the phonon modes in binary InN was an extrapolation of the Gai-xInxN (0 < x < 1) alloy modes in reflection towards the binary compound [1], A typically high free carrier concentration in the mid 1020 cm 3 range controls the absorption (Drude absorption) in the infrared and must also account for the broadened Reststrahlen band in pure InN films (e.g. in [1]). In this case infrared active phonons couple to the plasma of the free electrons forming phonon-plasmon coupled modes [10,11], However, layers of low carrier concentration have been achieved and pure LO phonon energies have been derived in Raman spectroscopy. Resonant Raman spectroscopy at 514 nm has been performed, assigning five of the six Raman allowed zone centre phonon modes [8,9] (TABLE 1). 

Despite resonant excitation conditions (Egmp(InN) 1.9 eV) the Raman spectrum of InN strongly resembles that of GaN although shifted to softer modes. Note, however, that the sequence of E2(LO) and Ai(LO) appears to be inverted compared to GaN. The Ei symmetry assignment of the reflection modes [1] was performed in [7] and by the present authors after a re-evaluation of the data. In addition, the large value of 694 cm 1 indicates an E1(LO)-plasmon coupled mode. It may be assumed that phonon frequencies in heteroepitaxial InN are subject to stress conditions in a similar way to that in heteroepitaxial GaN. 

The resistivity of a free-standing bulk sample was measured by depositing Pt electrodes by FIB and by employing the four point probe method [8], The resistivity of the bulk was 10 - 15 Q cm. The carrier concentration was estimated to be less than 1016 cm 3 by the plasmon-coupled mode in the Raman spectrum. These electrical measurements show that the crystal is of relatively high purity. 

The free carrier concentration at room temperature was determined by Raman experiments using the Ai(LO) phonon-plasmon coupled mode and by the reflectance in the mid-infrared and the optical absorption in the near-infrared range. Each experiment for the GaN layer of 60 pm thickness showed a free carrier concentration in the order of 1017 cm 3. 

Reinhard B, Sheikholeslami S, Mastroianni A, Alivisatos AP, Liphardt J. Use of plasmon coupling to reveal the dynamics of DNA bending and cleavage by single EcoRV restriction enzymes. Proc Natl Acad Sci USA 2007 104 2667-72. 

Sonnichsen C, Reinhard BM, Liphardt J, Alivisatos AP. A molecular ruler based on plasmon coupling of single gold and silver nanoparticles. Nat Biotechnol 2005 23 741-5. 

Watanabe K, Kim KH, Menzel D, Freund H-J. Hyperthermal chaotic photodesorption of xenon from alumina-supported silver nanoparticles plasmonic coupling and plasmon-induced desorption. Phys Rev Lett. 2007 99 225501. 

Here n is not a quantum number, but the charge density of Eq. (8.1.2).] If plasmons couple with photons, they form a plasma polariton. 

Kim D (2006) Effect of resonant localized plasmon coupling on the sensitivity enhancement of nanowire-based surface plasmon resonance biosensors. J Opt Soc Am A 23 2307-2314... 

Fig. 1 (a) Schematic representation of waveguide mode-surface plasmon coupling via k-vector match into a hybrid mode, (b) Experimental scheme of a planar waveguide with a small gold spot on its surface for transmission experiments... 

Fig. 2 Waveguide mode-surface plasmon coupling in fiber geometry with an area of removed cladding and a gold deposition therein, a) Experimental scheme for a single wavelength transmission experiment under controlled coupling angle a into the fiber, b) Experimental scheme for a spectral transmission experiment...

Fig. 3 Experimental scheme for a hollow optical fiber carrying a Bragg grating and a gold layer on the inner surface of the hollow fiber for waveguide mode-surface plasmon coupling and detection in transmission...

M. H. Chowdhury, S. N. Malyn, K. Aslan, J. R. Lakowicz, and C. D. Geddes. Multicolor directional surface plasmon-coupled chemiluminescence Journal of Physical Chemistry B, 2006, 110, 22644-22651. 

K. Aslan, M. J. Previte, Y. Zhang, and C. D. Geddes. Surface plasmon coupled fluorescence in the ultraviolet and visible spectral regions using zinc thin films Analytical chemistry, 2008, 80, 7304-7312. 

Matveeva, E.G., et al. (2005) Plastic versus glass support for an immunoassay on metal-coated surfaces in optically dense samples utilizing directional surface plasmon-coupled emissioa JFluoresc 15 865-71. 

In addition to plasmon coupling, fluorescent species placed near-to metallic nanoparticles experience an increase in their absorption of light (a modification in... 

Surface Plasmon Coupled Fluorescence Fiber Biosensing. Edited by Chris D. Geddes. 

Studies involved with evanescent wave excited surface plasmon coupled fluorescence... 

Micro-array Based on Localized Surface Plasmon Coupled Fluorescence... 

Hsieh B.-Y., Chang Y.-F., Ng M.-Y., Liu W.-C., Lin C.-H., Wu H.-T., and Chou C. (2007). Localized surface plasmon coupled fluorescence fiber-optic biosensor with gold nanoparticles. Anal. Chem. 79, 3487-3493. 

Borejdo, J. Gryczynski, Z. Calander, N. Muthu, P. Gryczynski, I. (2006) Application of Surface Plasmon Coupled Emission to Study of Muscle. Biophysical Journal 91 2626-2635. 

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