• Korean Journal of Optics and Photonics
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• v.17 no.6
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• pp.514-518
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• 2006

We have transferred highly stable 100 MHz RF through a 23 km fiber network. The fiber-induced phase noise due to the vibration and the temperature fluctuation in the optical path is detected and is compensated by configuring a noise-canceling servo. The transfer instability was $6{\times}10^{14}$ at 1 s of averaging time and $2{\times}10^{-17}$ at 10000 s of averaging time. The single sideband phase noise was greatly reduced by more than 20 dB below the Fourier frequency of 1 kHz. The transferred RF has nearly the same stability as the original reference frequency.

• Proceedings of the Korean Magnestics Society Conference
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• 2003.12a
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• pp.154-154
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• 2003

• Bulletin of the Korean Chemical Society
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• v.32 no.4
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• pp.1365-1367
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• 2011

• 한국초전도학회:학술대회논문집
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• v.13
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• pp.45-45
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• 2003

• 한국초전도학회:학술대회논문집
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• v.12
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• pp.54-54
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• 2002

• 한국초전도학회:학술대회논문집
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• v.12
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• pp.55-55
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• 2002

• Proceedings of the Optical Society of Korea Conference
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• 2008.02a
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• pp.257-258
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• 2008

• Journal of the Optical Society of Korea
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• v.7 no.3
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• pp.150-155
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• 2003

Femtosecond laser ablation mechanism was systematically investigated on sodalime glass in ambient conditions. The ablation crater diameter was measured for varying numbers of laser pulses as for varying well as the laser fluence. The analysis of the results with a one dimensional spatial Gaussian fluence distribution reveals that the inherent ablation mechanism has been altered from a multi-photon process to a single photon excitation due to defect sites that have been accumulated by successive laser pulses. Furthermore, the transition between the two regimes was found to be a function of both the laser fluence and the number of laser shots.

• Journal of Positioning, Navigation, and Timing
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• v.5 no.2
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• pp.67-74
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• 2016

In this paper, time comparison is performed with standardization institution in Japan using a Two-Way Satellite Time and Frequency Transfer (TWSTFT) technique as one of the methods for high precision time comparison. To analyze the performance of time comparison in the TWSTFT method, time comparison results via the Global Positioning System (GPS) code and carrier wave are analyzed. Through the time comparison performance, frequency stability is analyzed using modified Allan deviation and by this result, characteristics of time comparison of the TWSTFT that is utilized in international time comparison are presented.

• Proceedings of the Korean Magnestics Society Conference
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• 2014.05a
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• pp.25-25
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• 2014