Hybrid optoplasmonic microresonators and networks

Svetlana V. Boriskina* Wonmi Ahn, Yan Hong and Björn M. Reinhard Department of Chemistry & The Photonics Center, Boston University, Boston, MA

*e-mail: SBoriskina@gmail.com

Abstract: Hybrid optoplasmonic microresonator-based components will be discussed. They enable dynamical activation/switching of electromagnetic hot-spots, ultrasensitive bio(chemical) detection, and efficient photon generation, routing, and re-focusing into nanoscale volumes accessible to both far-field and on-chip detection.

High-Q optical microcavities such as e.g. microsphere and microdisks provide fascinating opportunities for controlling and harvesting light-matter interactions. In particular, their capability to resonantly manipulate the local density of electromagnetic states (LDOS) has already been shown to give rise to the amazingly rich physics and has been harnessed for a variety of practical applications in optical communications and sensing. In turn, noble-metal nanostructures that support localized surface plasmon (LSP) resonances offer unsurpassed capabilities for sub-wavelength light focusing and high sensitivity to environmental changes, which explains their rapidly expanding role in nanoimaging and biomedical research. While spectral positioning of the localized plasmon resonances can be achieved by varying nanoparticles morphology, dissipative losses in metallic nanostructures hinder efficient control over their plasmon resonances linewidths. These losses also limit the use of propagating SP polaritons as the long-distance signal carriers, which challenges construction of extended plasmonic nanocircuitries.

We will discuss the concept and applications of hybrid optoplasmonic structures that combine the capability of optical microcavities to insulate molecule-photon systems from decohering environmental effects with the superior light nanoconcentration properties of LSP nanoantennas (Fig. 1). We will show that optoplasmonic elements enable wavelength selectivity, long-range on-chip signal transfer and multiplexing capabilities without sacrificing the extreme light localization crucial for achieving tailored light interaction with quantum emitters [1]. As photon re-cycling in photonic microcavities greatly enhances the sensitivity of light to small changes in their refractive index, dynamically re-configurable plasmonic structures can also be realized [1,2]. Furthermore, hybrid optoplasmonic biosensing platforms combine high sensitivity of plasmonic elements with high spectral resolution of high-Q microcavity biosensors and thus can feature improved detection limits as compared to individual photonic and plasmonic sensors [3]. We will also discuss rational fabrication approaches for optoplasmonic networks and materials amenable to on-chip integration and operation.

Fig. 1. Configurable optoplasmonic nanocircuits with multiple spectral and spatial channels combine efficient light recycling & multiplexing capabilities with sub-wavelength localization.

The work was partially supported by the National Institutes of Health through grant 5R01CA138509-03, the National Science Foundation through grants CBET-0853798 and CBET-0953121 (BMR) and by the EU COST Action MP0702 “Towards functional sub-wavelength photonic structures” (SVB). 1. S.V. Boriskina and B.M. Reinhard, Proc. Natl. Acad. Sci. 108 (8), 3147-3151 (2011). 2. S.V. Boriskina and B.M. Reinhard, to appear in Opt. Express, Focus Issue Collective Phenomena in Photonic,

Plasmonic and Hybrid Structures (S.V. Boriskina et al Eds.) (2011). 3. M.A. Santiago-Cordoba, S.V. Boriskina, F. Vollmer, and M.C. Demirel, to appear in Appl. Phys. Lett. 15 Aug

(2011).

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TuA2 (Invited)9:00 AM – 9:30 AM

978-1-4244-8939-8/11/$26.00 ©2011 IEEE