Tung-Yu Su - Profile on Academia.edu (original) (raw)

Papers by Tung-Yu Su

Dependence of third-harmonic generation on melanin concentration in solution

Multiphoton Microscopy in the Biomedical Sciences XI, 2011

In this study, we performed theoretical analysis and experimental measurement of third harmonic g... more In this study, we performed theoretical analysis and experimental measurement of third harmonic generation (THG) in melanin solution with different concentrations. As predicted by theory, only THG at glass/solution interface was observed due to Guoy phase shift effect. We have shown that this interfacial THG intensity is strongly affected by index matching condition between the two media, leading to minimal

Relationship of second order susceptibility to the dimensions of ZnO nanorods based on Lorentz local field

Ultrafast Phenomena and Nanophotonics XVI, 2012

ABSTRACT

Modification of Point-Spread Function in Confocal Microscopy by Nonlinear Plasmonic Light Scattering

JSAP-OSA Joint Symposia 2014 Abstracts, 2014

Reverse saturable scattering of a single gold nanoparticle

Single Molecule Spectroscopy and Superresolution Imaging VII, 2014

ABSTRACT Recently, we discovered, for the first time, reverse saturable scattering in a single go... more ABSTRACT Recently, we discovered, for the first time, reverse saturable scattering in a single gold nanoparticle. When incident intensity increases, the scattering intensity dependence of 80-nm gold nanoparticles evolves from linear, to saturation, and to reverse saturation sequentially. The intensity dependence in reverse saturable scattering region is significantly steeper than that in the linear region. With the aid of a confocal microscope, the full width half maximum of the single-particle point spread function can be reduced down to 80 nm, which is beyond the diffraction limit. Our finding shows great potential for superresolution imaging application without bleaching.

Saturable scattering and its application to superresolution microscopy

2013 Conference on Lasers and Electro-Optics Pacific Rim (CLEOPR), 2013

Saturable scattering of localized surface plasmon resonance in a single gold nanoparticle

Plasmonics: Metallic Nanostructures and Their Optical Properties X, 2012

Saturable and Reverse Saturable Scattering of a Single Gold Nanoparticle

JSAP-OSA Joint Symposia 2013 Abstracts, 2013

Plasmon saturation induced super-resolution imaging

Plasmonics in Biology and Medicine X, 2013

Size and wavelength dependency of saturable scattering by a single gold nanosphere embedded in dielectric material

Plasmonics in Biology and Medicine XI, 2014

ABSTRACT The wavelength and size dependencies of nonlinear scattering by a single gold nanosphere... more ABSTRACT The wavelength and size dependencies of nonlinear scattering by a single gold nanosphere immersed in oil are presented. We show that the wavelength dependency fits well with the scattering spectrum by Mie solution, reflecting that the nonlinear scattering is dominated by the field enhancement from plasmonic effects. The tendency for different sizes is consistent with the results of degenerate four-wave mixing in the literature, showing that the saturation behavior is governed by the Kerr nonlinearity resonantly enhanced via intraband transition. Thus we conclude that the saturable scattering in our case is attributed to intraband χ(3), with nonlinear behavior enhanced by LSPR.

Measurement of a Saturated Emission of Optical Radiation from Gold Nanoparticles: Application to an Ultrahigh Resolution Microscope

Physical Review Letters, 2014

We show that scattering from a single gold nanoparticle is saturable for the first time. Waveleng... more We show that scattering from a single gold nanoparticle is saturable for the first time. Wavelength-dependent study reveals that the saturation behavior is governed by depletion of surface plasmon resonance, not the thermal effect. We observed interesting flattening of the point spread function of scattering from a single nanoparticle due to saturation. By extracting the saturated part of scattering via temporal modulation, we achieve λ/8 point spread function in far-field imaging with unambiguous separation of adjacent particles.

Effect of Lorentz local field for optical second order nonlinear susceptibility in ZnO nanorod

Journal of Applied Physics, 2012

ABSTRACT

On the possible origin of bulk third harmonic generation in skin cells

Applied Physics Letters, 2011

We studied third harmonic generation (THG) of melanin solution with concentrations similar to mel... more We studied third harmonic generation (THG) of melanin solution with concentrations similar to melanocytes in human skin. In contrast to conventional observation of THG at interface, bulk THG was detected inside the solution due to the formation of melanin hydrocolloids. A linear relationship between melanin concentration and THG intensity was found, suggesting THG originated from high-order hyper-Rayleigh scattering. By fitting

ACS Photonics, 2014

Nonlinear optical interaction is crucial to alloptical signal processing. In metallic nanostructu... more Nonlinear optical interaction is crucial to alloptical signal processing. In metallic nanostructures, both linear and nonlinear optical interactions can be greatly enhanced by surface plasmon resonance (SPR). In the last few decades, saturation and reverse saturation of absorption in plasmonic materials have been unraveled. It is known that scattering is one of the fundamental light−matter interactions and is particularly strong in metallic nanoparticles due to SPR. However, previous methods measure response from ensemble of nanoparticles and did not characterize scattering on a single particle basis. Here we report that backscattering from an isolated gold nanoparticle exhibits not only saturation, but also reverse saturation. Wavelength-dependent and intensitydependent studies reveal that nonlinear scattering is dominated by SPR and shares a similar physical origin with nonlinear absorption. The reversibility and repeatability of saturable scattering (SS) and reverse saturable scattering (RSS) are validated via repetitive excitation on the same set of particles. Compared to fluorescence, our novel discovery of single-particle-based SS and RSS does not suffer from bleaching and can be used as a more robust contrast agent for optical microscopy. Under a reflection confocal microscope, interesting point-spread functions are observed, with full-width-of-half-maximum of central and side lobes reduced to λ/5 and λ/13, showing great potential for superresolution microscopy.

Dependence of third-harmonic generation on melanin concentration in solution

Multiphoton Microscopy in the Biomedical Sciences XI, 2011

In this study, we performed theoretical analysis and experimental measurement of third harmonic g... more In this study, we performed theoretical analysis and experimental measurement of third harmonic generation (THG) in melanin solution with different concentrations. As predicted by theory, only THG at glass/solution interface was observed due to Guoy phase shift effect. We have shown that this interfacial THG intensity is strongly affected by index matching condition between the two media, leading to minimal

Relationship of second order susceptibility to the dimensions of ZnO nanorods based on Lorentz local field

Ultrafast Phenomena and Nanophotonics XVI, 2012

ABSTRACT

Modification of Point-Spread Function in Confocal Microscopy by Nonlinear Plasmonic Light Scattering

JSAP-OSA Joint Symposia 2014 Abstracts, 2014

Reverse saturable scattering of a single gold nanoparticle

Single Molecule Spectroscopy and Superresolution Imaging VII, 2014

ABSTRACT Recently, we discovered, for the first time, reverse saturable scattering in a single go... more ABSTRACT Recently, we discovered, for the first time, reverse saturable scattering in a single gold nanoparticle. When incident intensity increases, the scattering intensity dependence of 80-nm gold nanoparticles evolves from linear, to saturation, and to reverse saturation sequentially. The intensity dependence in reverse saturable scattering region is significantly steeper than that in the linear region. With the aid of a confocal microscope, the full width half maximum of the single-particle point spread function can be reduced down to 80 nm, which is beyond the diffraction limit. Our finding shows great potential for superresolution imaging application without bleaching.

Saturable scattering and its application to superresolution microscopy

2013 Conference on Lasers and Electro-Optics Pacific Rim (CLEOPR), 2013

Saturable scattering of localized surface plasmon resonance in a single gold nanoparticle

Plasmonics: Metallic Nanostructures and Their Optical Properties X, 2012

Saturable and Reverse Saturable Scattering of a Single Gold Nanoparticle

JSAP-OSA Joint Symposia 2013 Abstracts, 2013

Plasmon saturation induced super-resolution imaging

Plasmonics in Biology and Medicine X, 2013

Size and wavelength dependency of saturable scattering by a single gold nanosphere embedded in dielectric material

Plasmonics in Biology and Medicine XI, 2014

ABSTRACT The wavelength and size dependencies of nonlinear scattering by a single gold nanosphere... more ABSTRACT The wavelength and size dependencies of nonlinear scattering by a single gold nanosphere immersed in oil are presented. We show that the wavelength dependency fits well with the scattering spectrum by Mie solution, reflecting that the nonlinear scattering is dominated by the field enhancement from plasmonic effects. The tendency for different sizes is consistent with the results of degenerate four-wave mixing in the literature, showing that the saturation behavior is governed by the Kerr nonlinearity resonantly enhanced via intraband transition. Thus we conclude that the saturable scattering in our case is attributed to intraband χ(3), with nonlinear behavior enhanced by LSPR.

Measurement of a Saturated Emission of Optical Radiation from Gold Nanoparticles: Application to an Ultrahigh Resolution Microscope

Physical Review Letters, 2014

We show that scattering from a single gold nanoparticle is saturable for the first time. Waveleng... more We show that scattering from a single gold nanoparticle is saturable for the first time. Wavelength-dependent study reveals that the saturation behavior is governed by depletion of surface plasmon resonance, not the thermal effect. We observed interesting flattening of the point spread function of scattering from a single nanoparticle due to saturation. By extracting the saturated part of scattering via temporal modulation, we achieve λ/8 point spread function in far-field imaging with unambiguous separation of adjacent particles.

Effect of Lorentz local field for optical second order nonlinear susceptibility in ZnO nanorod

Journal of Applied Physics, 2012

ABSTRACT

On the possible origin of bulk third harmonic generation in skin cells

Applied Physics Letters, 2011

We studied third harmonic generation (THG) of melanin solution with concentrations similar to mel... more We studied third harmonic generation (THG) of melanin solution with concentrations similar to melanocytes in human skin. In contrast to conventional observation of THG at interface, bulk THG was detected inside the solution due to the formation of melanin hydrocolloids. A linear relationship between melanin concentration and THG intensity was found, suggesting THG originated from high-order hyper-Rayleigh scattering. By fitting

ACS Photonics, 2014

Nonlinear optical interaction is crucial to alloptical signal processing. In metallic nanostructu... more Nonlinear optical interaction is crucial to alloptical signal processing. In metallic nanostructures, both linear and nonlinear optical interactions can be greatly enhanced by surface plasmon resonance (SPR). In the last few decades, saturation and reverse saturation of absorption in plasmonic materials have been unraveled. It is known that scattering is one of the fundamental light−matter interactions and is particularly strong in metallic nanoparticles due to SPR. However, previous methods measure response from ensemble of nanoparticles and did not characterize scattering on a single particle basis. Here we report that backscattering from an isolated gold nanoparticle exhibits not only saturation, but also reverse saturation. Wavelength-dependent and intensitydependent studies reveal that nonlinear scattering is dominated by SPR and shares a similar physical origin with nonlinear absorption. The reversibility and repeatability of saturable scattering (SS) and reverse saturable scattering (RSS) are validated via repetitive excitation on the same set of particles. Compared to fluorescence, our novel discovery of single-particle-based SS and RSS does not suffer from bleaching and can be used as a more robust contrast agent for optical microscopy. Under a reflection confocal microscope, interesting point-spread functions are observed, with full-width-of-half-maximum of central and side lobes reduced to λ/5 and λ/13, showing great potential for superresolution microscopy.