• Proceedings of the Korean Society of Potoscience Conference
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• 2006.06a
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• pp.44-44
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• 2006

• Proceedings of the KIEE Conference
• /
• 2005.11a
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• pp.207-209
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• 2005

Ultra wide band electromagnetic energy can be transmitted to a far field by emitting the nanoseconds high voltage pulse electromagnetic energy via an antenna. This UWB EM energy is expected to be used in post-packing pasteurization of food, detection of buried objects or underground water veins and caves and the treatment of waste water or polluted gas. The nanoseconds pulse forming for UWB generation using high voltage blumlein line and an ultrafast switch is mentioned.

• Proceedings of the KIEE Conference
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• 1997.07e
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• pp.1859-1860
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• 1997

다전극 DFB(distributed feedback) 레이저서, 레이징모드간 비팅을 통하여 초고속으로 자려펄스열을 발생시킬 수 있음을 제안한다. 이러한 자려펄스생성을 수정된 시영역 동적 모델(large signal time-domain dynamic model)을 이용하여 조사하였다.

• Proceedings of the Korean Society of Laser Processing Conference
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• 2005.11a
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• pp.156-157
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• 2005

• Proceedings of the Optical Society of Korea Conference
• /
• 2005.07a
• /
• pp.216-217
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• 2005

• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.2123-2125
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• 2005

Ultra wide band electromagnetic energy can be transmitted to a far field by emitting the nanoseconds high voltage Pulse electromagnetic energy via an antenna. This UWB EM energy is expected to be used in post-packing pasteurization of food, detection of buried objects or underground water veins and caves and the treatment of waste water or polluted gas. The nanoseconds pulse forming for UWB generation using 500kV blumlein line and an ultrafast switch is mentioned.

• Journal of Photoscience
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• v.6 no.3
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• pp.123-128
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• 1999

Dynamics of many ultrafast processes are markedly slowed down in various organized molecular assemblies compared to ordinary liquids. We will show that the solvation dynamics of water molecules is affected amost dramatically and is retarded by 3 ∼4 orders of magnitude in microemulsions, micells and lipids. We will also discuss how the access to fewer water molucules and the drastically altered local pH in an organized asembly affected the excited state proton transfer processes. Finally, we will show how surface second haromonic generation can be used to study the air-water surface.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2011.06a
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• pp.249-250
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• 2011

• Current Optics and Photonics
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• v.6 no.6
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• pp.576-582
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• 2022

Plasmonic high-order harmonic generation (HHG) is used in nanoscale optical applications because it can help in realizing a compact coherent ultrashort pulse generator on the nanoscale, using plasmonic field enhancement. The plasmonic amplification of nanostructures induces nonlinear optical phenomena such as second-order harmonic generation, third-order harmonic generation, frequency mixing, and HHG. This amplification also causes damage to the structure itself. In this study, the plasmonic amplification according to the design of a metal-coated sapphire conical structure is theoretically calculated, and we analyze the effects of this optical amplification on HHG and damage to the sample.

• Journal of Photoscience
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• v.9 no.2
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• pp.122-125
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• 2002

Coherent oscillations in is fluorescence dynamics of W.-t. PYP and its site-directed mutants have been observed. Two oscillatory modes coupled with the ultrafast fluorescence due to the twisting of the excited chromophore were identified, a high ftequency mode (∼135 cm$\^$-1/) with ∼550 is damping time and a low frequency overdamped mode (-45 cm$\^$-1/) with ∼250 is damping time, respectively. Both modes disappear in the fluorescence dynamics of denatured PYP emphasizing the important role of the protein nanospace as the environment for photoreaction. The qualitative picture of fluorescence dynamics in site-directed mutants was rather similar to that in W.-t. PYP, i.e., similar oscillatory modes (∼130-140 cm$\^$-1/ and ∼40-70 cm$\^$-1/) have been observed. This indicates that the vibrational modes and electron-vibration couplings do not change dramatically due to the mutation though the damping time of low frequency mode a little decreases as the protein nanospace structure becomes looser and more disordered by mutation. On the other hand, in the case of some PYP analogues, the qualitative picture of fluorescence dynamics changes, showing the familiar picture of solvation effect whereas the oscillations are almost damped. Comparative analyses of these observations are presented.