Conference on Lasers and Electro-Optics/International Quantum Electronics Conference, 2009
Our simulations show that highly localized field enhancement produced by a periodic array of silv... more Our simulations show that highly localized field enhancement produced by a periodic array of silver nanoantennas can be translated to the far side of a metal-dielectric composite superlens composed of silver and silica components.
Abstract. A novel class of materials, fractal-microcavity composites, that pro-vides unprecented ... more Abstract. A novel class of materials, fractal-microcavity composites, that pro-vides unprecented enhancement of optical responses is developed. These composites combine the energy-concentrating effects due to localization of optical excitations in fractals with the strong morphology-...
Owing to the low-loss and high refractive index variations derived from the basic building block ... more Owing to the low-loss and high refractive index variations derived from the basic building block of bone structure, we, for the first time to our knowledge, demonstrate coherent random lasing action originated from the bone structure infiltrated with laser dye, revealing that bone tissue is an ideal biological material for random lasing. Our numerical simulation shows that random lasers are extremely sensitive to subtle structural changes even at nanoscales and can potentially be an excellent tool for probing nanoscale structural alterations in real time as a novel spectroscopic modality.
Near-field imaging of an engineered double layer structure in transmission mode has shown enhance... more Near-field imaging of an engineered double layer structure in transmission mode has shown enhancement of light intensity through the structure. An array created by an optically thick double layer structure of a total thickness of 165 nm containing twin 50 nm Au layers was imaged using a near-field scanning optical microscope in illumination mode. The resulting transmission image shows an increased local transmission at the position of each particle in the array. This viewable enhancement is due to a nanoantenna effect that is created by a resonant plasmon oscillation between the two layers.
Conference on Lasers and Electro-Optics 2010, 2010
We use spatial harmonic analysis (SHA) to model gold double-strip gratings under obliquely incide... more We use spatial harmonic analysis (SHA) to model gold double-strip gratings under obliquely incident light. The simulation results are compared to experimentally measured values and excellent matches are achieved.
Adaptive silver films (ASFs) have been studied as a substrate for protein microarrays. Vacuum eva... more Adaptive silver films (ASFs) have been studied as a substrate for protein microarrays. Vacuum evaporated silver films fabricated at certain range of evaporation parameters allow fine rearrangement of the silver nanostructure under protein depositions in buffer solution. Proteins restructure and stabilize the ASF to increase the surface-enhanced Raman scattering (SERS) signal from a monolayer of molecules. Preliminary evidence indicates that
Some recent papers [2],[3] report that the nonlinear susceptibility does not depend on quantum si... more Some recent papers [2],[3] report that the nonlinear susceptibility does not depend on quantum size effects. We show that this is not valid when considering the enchancement factor of one particle. Quantum size effects in nanoparticles not only exist but they have dominant contriubution. Our results in good agreement with the model proposed by Rautian [1].
We have studied the effect of aperture-sample interactions on the near-field optical imaging and ... more We have studied the effect of aperture-sample interactions on the near-field optical imaging and its application for plasmonic metamaterials. Specifically, periodic arrays of paired and single gold nanorods were studied at the near-field using reflection and transmission modes of a near-field scanning optical microscope (NSOM) at various wavelengths and polarizations of light in the visible range. The paired nanorods act
The efforts to construct media exhibiting negative refraction have been extended to the optical r... more The efforts to construct media exhibiting negative refraction have been extended to the optical range. In this work we present examples of structures with negative refraction at optical frequencies, including paired nanorods arrays and coupled metal strips. The negative refractive indices in such nanofabricated metamaterials result from plasmon resonances for both the electric and magnetic components of light at overlapping
Optical properties of metal nanowires and nanowire composite materials are studied experimentally... more Optical properties of metal nanowires and nanowire composite materials are studied experimentally and theoretically. We suggest that a nanowire composite, constructed from parallel pairs of nanowires has both effective magnetic permeability and dielectric permittivity negative in the visible and near-infrared spectral ranges due to resonant excitation of surface plasmon polaritons. Experimental results confirm excitation of surface plasmons polaritons in periodical
... It is known that the aggregation of even a few particles makes a large difference for ... in ... more ... It is known that the aggregation of even a few particles makes a large difference for ... in DI water 5 times), (c) after incubation with antigen cocktail containing 1nM human interleuikin 10. ... of R6G molecules can potentially be applied to binding detection and thus merits further study. ...
2010 14th Biennial IEEE Conference on Electromagnetic Field Computation (CEFC 2010), 2010
Metal nanoantenna arrays are typically designed and simulated using an ideal (smooth) geometry, a... more Metal nanoantenna arrays are typically designed and simulated using an ideal (smooth) geometry, and degraded experimental performance due to surface roughness, interior defects, and other effects are taken into account through a single value, a material `loss factor'; although a 2-D roughness has been introduced in simulations for plasmonic metamagnetics. Here, we aim to treat roughness independently from other types of loss by introducing a controlled roughened geometry into the FE model. The effect of various geometric defects on the resulting electromagnetic model, specifically, transmission and reflection spectra, will be presented.
2006 Conference on Lasers & Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS), 2006
Practical optical negative index materials based on coupled plasmon resonances must overcome refl... more Practical optical negative index materials based on coupled plasmon resonances must overcome reflection and absorption. Simulations show that matched impedance and compensated losses due to optimized design and gain material, respectively, lead to 100% transmission.
Conference on Lasers and Electro-Optics/International Quantum Electronics Conference, 2009
Our simulations show that highly localized field enhancement produced by a periodic array of silv... more Our simulations show that highly localized field enhancement produced by a periodic array of silver nanoantennas can be translated to the far side of a metal-dielectric composite superlens composed of silver and silica components.
Abstract. A novel class of materials, fractal-microcavity composites, that pro-vides unprecented ... more Abstract. A novel class of materials, fractal-microcavity composites, that pro-vides unprecented enhancement of optical responses is developed. These composites combine the energy-concentrating effects due to localization of optical excitations in fractals with the strong morphology-...
Owing to the low-loss and high refractive index variations derived from the basic building block ... more Owing to the low-loss and high refractive index variations derived from the basic building block of bone structure, we, for the first time to our knowledge, demonstrate coherent random lasing action originated from the bone structure infiltrated with laser dye, revealing that bone tissue is an ideal biological material for random lasing. Our numerical simulation shows that random lasers are extremely sensitive to subtle structural changes even at nanoscales and can potentially be an excellent tool for probing nanoscale structural alterations in real time as a novel spectroscopic modality.
Near-field imaging of an engineered double layer structure in transmission mode has shown enhance... more Near-field imaging of an engineered double layer structure in transmission mode has shown enhancement of light intensity through the structure. An array created by an optically thick double layer structure of a total thickness of 165 nm containing twin 50 nm Au layers was imaged using a near-field scanning optical microscope in illumination mode. The resulting transmission image shows an increased local transmission at the position of each particle in the array. This viewable enhancement is due to a nanoantenna effect that is created by a resonant plasmon oscillation between the two layers.
Conference on Lasers and Electro-Optics 2010, 2010
We use spatial harmonic analysis (SHA) to model gold double-strip gratings under obliquely incide... more We use spatial harmonic analysis (SHA) to model gold double-strip gratings under obliquely incident light. The simulation results are compared to experimentally measured values and excellent matches are achieved.
Adaptive silver films (ASFs) have been studied as a substrate for protein microarrays. Vacuum eva... more Adaptive silver films (ASFs) have been studied as a substrate for protein microarrays. Vacuum evaporated silver films fabricated at certain range of evaporation parameters allow fine rearrangement of the silver nanostructure under protein depositions in buffer solution. Proteins restructure and stabilize the ASF to increase the surface-enhanced Raman scattering (SERS) signal from a monolayer of molecules. Preliminary evidence indicates that
Some recent papers [2],[3] report that the nonlinear susceptibility does not depend on quantum si... more Some recent papers [2],[3] report that the nonlinear susceptibility does not depend on quantum size effects. We show that this is not valid when considering the enchancement factor of one particle. Quantum size effects in nanoparticles not only exist but they have dominant contriubution. Our results in good agreement with the model proposed by Rautian [1].
We have studied the effect of aperture-sample interactions on the near-field optical imaging and ... more We have studied the effect of aperture-sample interactions on the near-field optical imaging and its application for plasmonic metamaterials. Specifically, periodic arrays of paired and single gold nanorods were studied at the near-field using reflection and transmission modes of a near-field scanning optical microscope (NSOM) at various wavelengths and polarizations of light in the visible range. The paired nanorods act
The efforts to construct media exhibiting negative refraction have been extended to the optical r... more The efforts to construct media exhibiting negative refraction have been extended to the optical range. In this work we present examples of structures with negative refraction at optical frequencies, including paired nanorods arrays and coupled metal strips. The negative refractive indices in such nanofabricated metamaterials result from plasmon resonances for both the electric and magnetic components of light at overlapping
Optical properties of metal nanowires and nanowire composite materials are studied experimentally... more Optical properties of metal nanowires and nanowire composite materials are studied experimentally and theoretically. We suggest that a nanowire composite, constructed from parallel pairs of nanowires has both effective magnetic permeability and dielectric permittivity negative in the visible and near-infrared spectral ranges due to resonant excitation of surface plasmon polaritons. Experimental results confirm excitation of surface plasmons polaritons in periodical
... It is known that the aggregation of even a few particles makes a large difference for ... in ... more ... It is known that the aggregation of even a few particles makes a large difference for ... in DI water 5 times), (c) after incubation with antigen cocktail containing 1nM human interleuikin 10. ... of R6G molecules can potentially be applied to binding detection and thus merits further study. ...
2010 14th Biennial IEEE Conference on Electromagnetic Field Computation (CEFC 2010), 2010
Metal nanoantenna arrays are typically designed and simulated using an ideal (smooth) geometry, a... more Metal nanoantenna arrays are typically designed and simulated using an ideal (smooth) geometry, and degraded experimental performance due to surface roughness, interior defects, and other effects are taken into account through a single value, a material `loss factor'; although a 2-D roughness has been introduced in simulations for plasmonic metamagnetics. Here, we aim to treat roughness independently from other types of loss by introducing a controlled roughened geometry into the FE model. The effect of various geometric defects on the resulting electromagnetic model, specifically, transmission and reflection spectra, will be presented.
2006 Conference on Lasers & Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS), 2006
Practical optical negative index materials based on coupled plasmon resonances must overcome refl... more Practical optical negative index materials based on coupled plasmon resonances must overcome reflection and absorption. Simulations show that matched impedance and compensated losses due to optimized design and gain material, respectively, lead to 100% transmission.
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