Plasmon-enhanced luminescence near noble-metal nanospheres: Comparison of exact theory and an improved Gersten and Nitzan model

We present a theoretical study of the modifications of the radiative and nonradiative decay rates of an optical emitter in close proximity to a noble-metal nanosphere, based on exact electrodynamical theory. We show that the optimal nanosphere diameter for luminescence quantum efficiency enhancement associated with resonant coupling to plasmon modes is in the range of $30--110\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$, depending on the material properties. The optimal diameter is found to be a trade-off between (1) emitter-plasmon coupling, which is most effective for small spheres, and (2) the outcoupling of plasmons into radiation, which is most efficient for large spheres. In addition, we show that the well-known Gersten and Nitzan model does not describe the existence of a finite optimal diameter unless the model is extended with the correction factor for radiation damping. With this correction and a correction for dynamic depolarization, the mathematically simpler Gersten and Nitzan model provides a reasonably accurate approximation of the decay rate modifications associated with coupling to the dipole plasmon mode. We anticipate that the Gersten and Nitzan model in the form that we validate in this paper for spheres will allow the analytical investigation of the influence of shape anisotropy on plasmon-enhanced luminescence.

[1]  R. Silbey,et al.  Molecular Fluorescence and Energy Transfer Near Interfaces , 2007 .

[2]  A. Polman,et al.  Plasmon-enhanced erbium luminescence , 2006 .

[3]  H. Atwater,et al.  Polarization-selective plasmon-enhanced silicon quantum-dot luminescence. , 2006, Nano letters (Print).

[4]  Jean-Jacques Greffet,et al.  Radiative and non-radiative decay of a single molecule close to a metallic nanoparticle , 2006 .

[5]  V. Sandoghdar,et al.  Enhancement of single-molecule fluorescence using a gold nanoparticle as an optical nanoantenna. , 2006, Physical review letters.

[6]  Nathan S. Lewis,et al.  Spectral tuning of plasmon-enhanced silicon quantum dot luminescence , 2006 .

[7]  L. Novotný,et al.  Enhancement and quenching of single-molecule fluorescence. , 2006, Physical review letters.

[8]  Stefan A Maier,et al.  Plasmonic field enhancement and SERS in the effective mode volume picture. , 2006, Optics express.

[9]  J. Lakowicz.  Plasmonics in Biology and Plasmon-Controlled Fluorescence , 2006, Plasmonics.

[10]  D. Pohl,et al.  Single quantum dot coupled to a scanning optical antenna: a tunable superemitter. , 2005, Physical review letters.

[11]  O. Martin,et al.  Resonant Optical Antennas , 2005, Science.

[12]  C. Henkel,et al.  Spontaneous emission in a subwavelength environment characterized by boundary integral equations , 2004 .

[13]  F. G. D. Abajo,et al.  Spontaneous light emission in complex nanostructures , 2004 .

[14]  E. Coronado,et al.  The Optical Properties of Metal Nanoparticles: The Influence of Size, Shape, and Dielectric Environment , 2003 .

[15]  D. Reinhoudt,et al.  Fluorescence quenching of dye molecules near gold nanoparticles: radiative and nonradiative effects. , 2002, Physical review letters.

[16]  V. Letokhov,et al.  Spontaneous emission of an atom placed near a prolate nanospheroid , 2002 .

[17]  D. Bergman,et al.  Localization versus delocalization of surface plasmons in nanosystems: can one state have both characteristics? , 2001, Physical review letters.

[18]  Lewei Li,et al.  Spheroidal vector wave eigenfunction expansion of dyadic Green's functions for a dielectric spheroid , 2001 .

[19]  H. T. Dung,et al.  Decay of an excited atom near an absorbing microsphere , 2000, quant-ph/0012103.

[20]  C. Haynes,et al.  Nanosphere lithography: Tunable localized surface plasmon resonance spectra of silver nanoparticles , 2000 .

[21]  H. T. Dung,et al.  Spontaneous decay in the presence of dispersing and absorbing bodies: General theory and application to a spherical cavity , 2000, quant-ph/0003138.

[22]  Reginald K. Lee,et al.  Quantum analysis and the classical analysis of spontaneous emission in a microcavity , 2000 .

[23]  E. Palik.  Handbook of Optical Constants of Solids , 1997 .

[24]  William L. Barnes,et al.  Modification of the spontaneous emission rate of Eu 3+ ions close to a thin metal mirror , 1997 .

[25]  L. Novotný.  Single molecule fluorescence in inhomogeneous environments , 1996 .

[26]  David D. Nolte,et al.  Optical scattering and absorption by metal nanoclusters in GaAs , 1994 .

[27]  M. Quinten,et al.  Absorption and elastic scattering of light by particle aggregates. , 1993, Applied optics.

[28]  P. Leung,et al.  Radiative decay rates for molecules near a dielectric sphere , 1988 .

[29]  M. Meier,et al.  Enhanced fields on large metal particles: dynamic depolarization. , 1983, Optics letters.

[30]  James P. Gordon,et al.  Radiation Damping in Surface-Enhanced Raman Scattering , 1982 .

[31]  R. Ruppin,et al.  Decay of an excited molecule near a small metal sphere , 1982 .

[32]  A. Nitzan,et al.  Spectroscopic properties of molecules interacting with small dielectric particles , 1981 .

[33]  Young Sik Kim,et al.  Classical decay rates for molecules in the presence of a spherical surface: A complete treatment , 1988 .

[34]  C. Tai,et al.  Dyadic green functions in electromagnetic theory , 1994 .

[35]  E. Purcell,et al.  Resonance Absorption by Nuclear Magnetic Moments in a Solid , 1946 .