• Title/Summary/Keyword: Nanoscale

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Bio-inspired Structural Colors of Transparent Substrate based on Light Diffraction and Interference on Microscale and Nanoscale Structures (자연모사기반 나노-마이크로패턴의 광 회절 및 간섭에 의한 투명기판의 구조색 구현)

  • Park, Yong Min;Kim, Byeong Hee;Seo, Young Ho
    • Journal of Industrial Technology
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    • v.39 no.1
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    • pp.33-39
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    • 2019
  • This paper addresses effects of nanoscale structures on structural colors of micropatterned transparent substrate by light diffraction. Structural colors is widely investigated because they present colors without any chemical pigments. Typically structural colors is presented by diffraction of light on a micropatterned surface or by multiple interference of light on a surface containing a periodic or quasi-periodic nano-structures. In this paper, each structural colors induced by quasi-periodic nano-structures, periodic micro-structures, and nano/micro dual structures is measured in order to investigate effects of nanoscale and microscale structures on structural colors in the transparent substrate. Using pre-fabricated pattern mold and hot-embossing process, nanoscale and microscale structures are replicated on the transparent PMMA(Poly methyl methacrylate) substrate. Nanoscale and microscale pattern molds are prepared by anodic oxidation process of aluminum sheet and by reactive ion etching process of silicon wafer, respectively. Structural colors are captured by digital camera, and their optical transmittance spectrum are measured by UV/visible spectrometer. From experimental results, we found that nano-structures provide monotonic colors by multiple interference, and micro-structures induce iridescent colors by diffraction of light. Structural colors is permanent and unchangeable, thus it can be used in various application field such as security, color filter and so on.

Comprehensive study of internal modals interactions: Comparison of various axial nonlinear beam theories

  • Somaye Jamali Shakhlavi;Reza Nazemnezhad
    • Advances in nano research
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    • v.16 no.3
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    • pp.273-288
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    • 2024
  • The geometrical nonlinear vibrations of the gold nanoscale rod are investigated for the first time by considering the internal modals interactions using different nonlinear beam theories. This phenomenon is usually one of the important features of nonlinear vibration systems. For a more detailed analysis, the von-Karman effects, preserving all the nonlinear terms in the strain-displacement relationships of gold nanoscale rods in three displacement directions, are considered to analyze the nonlinear axial vibrations of gold nanoscale rods. It uses highly accurate analytical-numerical solutions for the clamped-clamped and clamped-free boundary conditions of nanoscale gold rods. Also, with the help of Hamilton's principle, the governing equation and boundary conditions are derived based on Eringen's theory. The influence of nonlinear and nonlocal factors on axial vibrations was investigated separately for all three theories: Simple (ST), Rayleigh (RT) and Bishop (BT). Using different theories, the effects of inertia and shear on the internal resonances of gold nanorods were studied and compared in terms of twoto-one and three-to-one internal resonances. As the nonlocal parameter of the gold nanorod increases, the maximum nonlinear amplitude occurs. So, by adding nonlocal effects in a gold nanorod, the internal modal interactions resulting from the unique structure can be enhanced. It is worth noting that shear and inertial analysis have a significant effect on internal modal interactions in gold nanorods.

Characterization of Ultrathin Gate Dielectrics for Nanoscale CMOS Applications

  • Yoon, Gi-Wan;Mai, Linh;Lee, Jae-Young
    • Journal of information and communication convergence engineering
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    • v.5 no.2
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    • pp.109-111
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    • 2007
  • In this paper, MOS devices with ultrathin gate dielectrics (5.5 nm) are characterized and compared with those with conventional oxides particularly for nanoscale CMOS applications. Nitrogen concentrations and profiles in the nitride gate dielectrics were obtained that will play an important role in improving both hot-carrier lifetime and resistance to boron penetration. This approach seems very useful for future nanoscale CMOS device applications.

NEIGHBORHOOD STRUCTURES IN ORDINARY SMOOTH TOPOLOGICAL SPACES

  • Lee, Jeong Gon;Lim, Pyung Ki;Hur, Kul
    • Honam Mathematical Journal
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    • v.34 no.4
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    • pp.559-570
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    • 2012
  • We construct a new definition of a base for ordinary smooth topological spaces and introduce the concept of a neighborhood structure in ordinary smooth topological spaces. Then, we state some of their properties which are generalizations of some results in classical topological spaces.

Vague Continuous Mappings

  • Lim, Pyung-Ki;Kim, So-Ra;Hur, Kul
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.10 no.2
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    • pp.157-164
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    • 2010
  • Up to now, in the area of fuzzy topology, almost all the researchers have investigated fuzzy continuities by using ordinary mappings. However, in this paper, we study continuities by using fuzzy mappings introduced by Demirci [2].

Probing of Surface Potential Using Atomic Force Microscopy

  • Kwon, Owoong;Kim, Yunseok
    • Applied Microscopy
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    • v.44 no.3
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    • pp.100-104
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    • 2014
  • As decreasing device size, probing of nanoscale surface properties becomes more significant. In particular, nanoscale probing of surface potential has paid much attention for understanding various surface phenomena. In this article, we review different atomic force microscopy techniques, including electrostatic force microscopy and Kelvin probe force microscopy, for measuring surface potential at the nanoscale. The review could provide fundamental information on the probing method of surface potential using atomic force microscopy.

The Category VSet(H)

  • Lim, Pyung-Ki;Kim, So-Ra;Hur, Kul
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • v.10 no.1
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    • pp.73-81
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    • 2010
  • We introduce the new category VSet(H) consisting of H-fuzzy spaces and H-fuzzy mappings between them satisfying a certain condition, and investigate VSet(H) in the sense of a topological universe. Moreover, we show that VSet(H) is Cartesian closed over Set.