• Current Optics and Photonics
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• v.7 no.6
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• pp.721-731
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• 2023

This paper studies various roughness parameters, besides waviness, texture, and nonlinear parameters of Bismarck brown Y (BBY)-doped Poly(methyl methacrylate) (PMMA) films based on the computed values of optical limiting (OL) threshold power and nonlinear refractive index. The films' morphology, grain size, and absorption spectra were investigated using atomic force microscopy in conjunction with ultraviolet-visible (UV-Vis) spectrophotometer. The particle size of the films ranged between 4.11-4.51 mm and polymer films showed good homogeneity and medium roughness, ranging from 1.11-4.58 mm. A polymer film's third-order nonlinear optical features were carried out using the Z-scan methodology. The measurements were obtained by a continuous wave produced from a solid-state laser with a 532 nm wavelength. According to the results, BBY has a nonlinear refractive index of 10^-6 cm²/W that is significantly negative and nonlinear. The optical limiting thresholds are roughly 10.29, 13.52, and 18.71 mW, respectively. The shift of nonlinear optical features with the film's concentration was found throughout the experiment Additionally, we found that the polymer samples have outstanding capabilities for restricting the amount of optical power that may be transmitted through them. We propose that these films have the potential to be used in a wide variety of optoelectronic applications, including optical photodetectors and optical switching.

• Korean Journal of Optics and Photonics
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• v.5 no.1
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• pp.31-36
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• 1994

We present a structure of a reflective Fabry-Perot etalon with nonlinear Kerr material (Kerr FP etalon), and report the polarization conversion and the optical bistability of polarization conversion. A device proposed has high polarization conversion ratio, 100% or so, and good/broad optical bistablity for input pump intensity.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.5 no.2
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• pp.181-188
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• 1995

3차 비선형광학 재료를 설계하기 위해 단성분 산화물에서의 산소의 평균 전자분극률과 광학 염기도를 굴절율, 에너지 갭의 각기 다른 물성을 통해 산출하였다. Lorentz-Lornez식과 Duffy 의 반실험식을 도입하여 산소의 평균 전자분극율과 광학 염기도를 두가지 다른 물성으로부터 계산하여 비교하였다. 처음으로 독립적인 초기값에서 계산한 각각의 산소의 평균 전자분극률과 광학 염기도 사이에 좋은 상응관계가 있음을 확인하였다.

• Proceedings of the IEEK Conference
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• 2000.06a
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• pp.244-247
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• 2000

This paper deals with methods for partial response maximum-likelihood (PRML) detection and crosstalk cancellation. In accrodance with the demand for increased recording density, 20 gigabyte (Gbyte) digital versatile disk (DVD) ROM channel is considered. Channel is modelled to be close to real optical channel using DIFFRACT$\^$TM/. After comparing the spectral characteristics of various PR polynomials, P(D)=1＋D＋D$^2$＋D$^3$is proposed as a target PR. The performance of the system is illustrated under the condition that the readout signal is degraded by crosstalk, radial tilt and nonlinear distortions in optics. The experimental results show that crosstalk and nonlinear distortions degrade performance by about 2dB, respectively. We also show that when radial tilt is added to the crosstalk, the performance degradation assumes quite significant proprotions.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.6 no.4
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• pp.272-277
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• 2013

In this paper the effect of instability and chaos in optical fiber networks based on the Internet is described. Nonlinear optical fiber effect especially Brillouin scattering in networks has emerged as the essential means for the construction of active optical devices used for all-optic in-line switching, channel selection, amplification, oscillation in optical communications and a host of other applications. The inherent optical feedback by the back-scattered Stokes wave in optical networks also leads to instabilities in the form of optical chaos. This paradigm of optical chaos in fiber Internet serves as a test for fundamental study of chaos and its suppression and exploitation in practical application in optical fiber communication. This paper attempts to present a survey and some of our research findings on the nature of Brillouin chaotic effect on Internet based optical communication.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.1 no.1
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• pp.61-66
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• 2008

In this paper the effect of instability and chaos in optical fiber networks based on the Internet is described. Nonlinear optical fiber effect especially Brillouin scattering in networks has emerged as the essential means for the construction of active optical devices used for all-optic in-line switching, channel selection, amplification, oscillation in optical communications and a host of other applications. The inherent optical feedback by the back-scattered Stokes wave in optical networks also leads to instabilities in the form of optical chaos. This paradigm of optical chaos in fiber Internet serves as a test for fundamental study of chaos and its suppression and exploitation in practical application in optical fiber communication. This paper attempts to present a survey and some of our research findings on the nature of Brillouin chaotic effect on Internet based optical communication.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1998.06a
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• pp.3-5
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• 1998

The interest in the use of borate crystals in ultraviolet(UV) nonlinear optics(NLO) has increased because all solid-stste UV lasers obtained with NLO are in highly demand. Much effort has been spent on developing borates series, such as{{{{ { beta -BaB }_{2 } {O }_{4 }(BBO), {LiB }_{ 3}{O }_{5 }(LBO)}}}} and{{{{{ CsKiB}_{6 }{O }_{10 }(CLBO)}}}} in this decade. Recently another new borate crystals, {{{{{ YCa}_{4 }O({BO }_{3 })_{3}}}}} and{{{{{Gd }_{x }{Y }_{1-x }{Ca }_{4 }O({BO }_{ 3})({Gd }_{x }{Y }_{1-x }COB)}}}} have been developed by the present authors. Here, the growth and NLO properties of YCOB and {{{{ {Gd }_{ x} {Y }_{ 1-x} }}}}CO B crystal are reported and their properties discussed in relation to those of other nonlinear optical crystals, such as LBO.

• Korean Journal of Optics and Photonics
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• v.5 no.1
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• pp.67-73
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• 1994

The simulation code was developed to analyze the amplification properties of the regenerative amplifier, such as gain narrowing, nonlinear effect, and energy saturation. To reduce gain narrowing in the regenerative amplifier, the input pulse with a symmetrical shape and the same center wavelength of the active medium should be amplified in the active medium with a broad fluorescence linewidth. In this respect, Ti:Sapphire with a low nonlinear refractive index, a high saturation fluence, and a broad fluorescence linewidth is the most appropriate medium for the regenerative amplifier. The knowledge and the important parameters were acquired for the optimum design of the regenerative amplifier.

• Journal of the Korean Ceramic Society
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• v.35 no.5
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• pp.493-498
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• 1998

ZnS doped borosilicate glass for nonlinear optical application was prepared by melting and precipitation process. The optical band gap of the precipitated ZnS particles ranged from 3.83 to 3.96 eV compared with the bulk ZnS energy gap of 3.53 eV. This result was interpreted in terms of a quantum confinement effect due to small crystal size. ZnS partilcle size estimated by effective mass approximation ranged from about 39 to 83 $\AA$ It increased wtih the increase of heat tratment time and temperature.

• Transactions of the Society of Information Storage Systems
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• v.10 no.1
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• pp.19-22
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• 2014

Optical nonlinear property is utilized to the wave generation, generating the beam at intended wavelength, and optical computing systems. The genetic material, which is the DNA with helical structure in nano-scale, is fascinating for optics communities due to artificially controllable sequence that determines the physical and chemical property. Nonlinearity of DNA was investigated by the four wave mixing experiment, which is with two incident beams located at 1550nm and 1650nm. The four output beams including incident beams are emitted from genetic material such as 1461nm and 1763nm by nonlinear characteristic. The 1461nm beam which is generated by four wave mixing phenomena was observed by optical spectrum analyzer.