Session 3A2b
Plasmonic Nanophotonics I - Experiment
Surface Plasmon Modulation in Silver Nanowires Revealed by Quantum Dot Fluorescence Imaging
Hong Wei, Hongxing Xu, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Hybrid Plasmonic Structures Design and Fabrication by Laser Means
Minghui Hong, L. Xu, N. T. V. Thanh, M. Tang, Z. C. Chen, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Localized Surface Plasmon Resonance of Arrayed Metallic Nano-structures Fabricated by Metal Contact
Printing Lithography
Hao-Yuan Chung, Chun-Ying Wu, Chun-Hung Chen, Yung-Chun Lee, . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Speed-up the Nanoelectronics with Plasmonics Technology
Er Ping Li, Ping Bai, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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Progress In Electromagnetics Research Symposium Abstracts, KL, MALAYSIA, March 27–30, 2012
Surface Plasmon Modulation in Silver Nanowires Revealed by
Quantum Dot Fluorescence Imaging
Hong Wei and Hongxing Xu
Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
Abstract— Plasmonic nanostructures show many interesting and valuable properties due to
surface plasmon (SP) resonances, and are extensively investigated for their potential applications
in different fields. Recently, the propagation of SPs in Ag nanowires (NWs) has received increasing
attention. We have shown the remote excitation of Raman scattering and quantum dot (QD)
fluorescence by using the propagating SPs in Ag NWs.
For Ag NWs coated by a layer of semiconductor QDs with dielectric spacer layer between them,
the QDs will be excited when plasmons propagate along the NW. Excitation of the QDs is
proportional to the local electric field intensity, allowing us to clearly visualize the plasmoninduced field distribution at every point along the NW. Quasi-periodic spatial modulation is
observed for the near field of propagating SPs (Fig. 1) [1]. The spatial modulation is formed by
the interference of different plasmon modes excited on the NW, and can be controlled by tuning
the incident polarization.
In simple NW networks, the QD imaging method can provide us a clear picture of how plasmons
can be redirected by and to additional proximal NWs at specific points along a primary NW.
Interference between SPs launched at different positions along a primary NW can turn on or off
emission paths, resulting in combinations of optical signals that execute specific interferometric
Boolean logic operations. This primary NW can thus be viewed as the plasmonic equivalent of a
bus in a central processing unit. In addition, a plasmonic NOR gate, one of the so-called “universal logic gates”, is demonstrated by cascading OR and NOT gates in four-terminal plasmonic
NW networks [2]. These findings shed new light onto fundamental understanding of propagating
plasmons in complex networks, and may advance the development of novel nanophotonic on-chip
processor architectures for future optical computing and information technologies.
Figure 1: (i) Optical image of a NW. (ii) The QD emission image with wide field excitation. (iii–vi)
QD emission images for different incident polarizations. The scale bar is 5 µm. The red arrows show the
polarization of excitation light.
REFERENCES
1. Wei, H., et al., Nano Lett., Vol. 11, 471–475, 2011.
2. Wei, H., et al., Nat. Commun., Vol. 2, 387, 2011.
Progress In Electromagnetics Research Symposium Abstracts, KL, MALAYSIA, March 27–30, 2012
Hybrid Plasmonic Structures Design and Fabrication by Laser
Means
M. H. Hong, L. Xu, N. T. V. Thanh, M. Tang, and Z. C. Chen
Department of Electrical and Computer Engineering
National University of Singapore, 10 Kent Ridge Crescent, 117576, Singapore
Abstract— Surface plasmon resonance (SPR) is a powerful means to achieve the localized enhancement of the optical field by forming “hot spots” on the metallic nanostructures to increase
signal detection sensitivity. SPR peak wavelength can be flexibly tuned by manipulating metallic nanoparticles or nanostructures’ sizes, shapes, thin film materials, and their inter-coupling.
Optical signal is increased greatly near or at the SPR peak wavelength with a sharp peak distribution. By coupling the molecules on the plasmonic structures, the resonance peak shift due to
the surrounding medium refractive index change can be used to characterize the molecules properties. However, this high Q resonance is typically corresponding to only one specific wavelength,
which limits its applications for wideband spectrum response devices, such as for high efficiency
solar cells in which Sunlight covers a light spectrum from 300 nm to 3 µm. It is an inevitable
need to design and fabricate hybrid plasmonic structures, which can work in a broadband. In
this talk, the synthesis of Ag : TiO2 nanocomposites by pulsed laser ablation in liquid is carried
out. By coupling in Ag nanoparticles, TiO2 optical properties can be modified with an additional resonance peak at visible light range to enhance the light absorption for photo-catalyst
and solar cell applications. Meanwhile, SPR can be tuned as well by modifying single-element
metallic thin film patterns from nanodots, to nanorods, and to nanodiamonds shapes by laser interference lithography. Bio-sensing of DNA molecules on large area Au nanorods surfaces shows
an amplified Fano-like shape resonance. Meanwhile, multi-element metallic alloy (Ag/Au and
Ag/Au/Cr) thin films and their nanostructures are fabricated to achieve multi-peak SPR. These
hybrid plasmonic structures can be used to make wideband anti-reflection black Si surfaces to
increase Sunlight absorption. Furthermore, laser micro-lens array (MLA) lithography is also
applied to make arbitrary plasmonic structures from optical, NIR to THz spectra. To further
reduce the metallic nanostructures down to 50 nm over a large area, thermal de-wetting of the
laser nanopatterned periodic structures is also carried out, which leads to better optical sensing
performance.
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Progress In Electromagnetics Research Symposium Abstracts, KL, MALAYSIA, March 27–30, 2012
Localized Surface Plasmon Resonance of Arrayed Metallic
Nano-structures Fabricated by Metal Contact Printing
Lithography
Hao-Yuan Chung, Chun-Ying Wu, Chun-Hung Chen, and Yung-Chun Lee
Department of Mechanical Engineering, National Cheng-Kung University, Tainan, Taiwan, R.O.C.
Abstract— In this study, we demonstrate a rapidly, low-cost, large-area, and mass productive
fabrication process to obtain arrayed metallic nanostructures on a variety of substrates. The key
element in this fabrication method is to combine an innovative metal contact printing lithography with conventional lifting-off and thermal annealing processes. Hexagonal arrays of metallic
nano-particles with sub-micron periodicity are successfully deployed on an ITO/glass substrate.
The dimensions, shapes, and arrangements of these arrayed metallic nano-structures and nanoparticles can be easily adjusted by using different pattern designs in the imprinting molds. The
sizes and material compositions of the obtained metal nano-particles can be easily controlled by
the deposition thicknesses and material varieties of films deposited during the sample preparation
process.
Optical transmittance measurements show that certain kinds of noble metallic arrayed nanoparticles deployed on an ITO/glass substrate can result in a phenomenal narrowband of extinction in
spectral range of visible light. Theoretical analysis indicates this narrowband extinction spectrum
is associated with electromagnetic field coupling between the arrayed metallic nanostructures and
the underlying ITO layer. Numerical simulation based on finite-difference time-domain method
(FDTD) is carried out to demonstrate the electromagnetic field distributions of the localized
surface plasmon resonance of arrayed metallic nanostructures and the excited waveguide modes
within the ITO layer. This electromagnetic field coupling induces significant plasmon resonance
in the ITO layer underneath the arrayed metallic nanostructures. A further evidence is attained
by comparing the measured transmittance spectrum of a similar noble metallic arrayed nanoparticles deployed on a glass substrate. Experimental results show that the narrowband extinction
in visible spectrum is vanished since there is no ITO layer to support guided modes resonance.
Based on this observed phenomenon and our innovative large-area nano-fabrication processes, optoelectronic devices with arrayed metallic nanostructures can be easily designed and developed
in the future.
Progress In Electromagnetics Research Symposium Abstracts, KL, MALAYSIA, March 27–30, 2012
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Speed-up the Nanoelectronics with Plasmonics Technology
Er Ping Li1, 2 and Ping Bai1
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2
Department of Electronics and Photonics, A*STAR-IHPC, Singapore
Department of Information Technology and Electronic Engineering, Zhejiang University, China
Abstract— The integration of optical devices into electronic circuits can achieve both the
advantages of ultra-compactness in electronics and super-wide bandwidth in optics. However, the
dimensions of traditional optical devices are fundamentally limited by the law of diffraction and
consequently limit the progress of merging photonic circuits with electronics. Plasmonics emerges
as a promising technology platform towards deployment of small-footprint integrated-circuitry
for chip-scale and high density integration, and could bridge the gap between the conventional
optics and nanoelectronics. In this talk, I will present the latest progress in the Institute of
High Performance Computing (IHPC) on plasmonics applications for optic data transmission in
electronic integrated circuits. A waveguide platform based on a hybrid plasmonic waveguide has
been demonstrated with CMOS-compatible technology, and used as a building block to build highperformance plasmonic devices, including bends, filters, splitters, and modulators. Plasmonic
detectors based on antennas and resonant cavities will also be discussed. With the developed
plasmonic devices, plasmonic circuits could be implemented to transmit signals optically on a
chip.
ACKNOWLEDGMENT
This work was supported by the A*STAR Metamaterials-Nanoplasmonics research programme
under grant A*STAR-SERC 0921540098.
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Progress In Electromagnetics Research Symposium Abstracts, KL, MALAYSIA, March 27–30, 2012