FEL2017 - List of Authors (Masuda, K.)

Paper	Title	Page
MOP050	Present Status of Infrared FEL Facility at Kyoto University	162
	H. Zen, T. Kii, S. Krainara, K. Masuda, H. Ohgaki, J. Okumura, S. Suphakul, S. Tagiri, K. Torgasin Kyoto University, Kyoto, Japan
	A mid-infrared free electron laser (FEL) named KU-FEL has been developed for promoting energy-related research at the Institute of Advanced Energy, Kyoto University.* KU-FEL can cover the wavelength range from 3.6 to 23 micrometers and is routinely operated for internal and external user experiments. Recently a THz Coherent Undulator Radiation (CUR) source using a photocathode RF gun has been developed as an extension of the facility.* As the result of commissioning the experiment, it was confirmed that the CUR source can cover the frequency range from 160 to 550 GHz. Present status of these infrared light sources will be presented. * H. Zen et al., Physics Procedia 84, pp.47-53 (2016).
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2017-MOP050
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WEP014	Pulse Duration Measurement of Pico-second DUV Photocathode Driving Laser by Autocorrelation Technique Using Two-Photon Absorption in Bulk Material	447
	H. Zen, T. Kii, K. Masuda, T. Nakajima, H. Ohgaki Kyoto University, Kyoto, Japan
	A multi-bunch, pico-second DUV photocathode drive laser system has been developed for photocathode operation of mid-infrared free electron laser facility, KU-FEL.* By using the laser, KU-FEL has already succeeded in first lasing under the photocathode operation. The pulse duration of the photocathode driving laser is a quite important parameter because it determines the initial electron pulse duration on the cathode surface. However, the pulse duration of the photocathode driving laser had not been characterized. A very convenient pulse duration measurement method utilizing two-photon absorption in bulk material, which can be used for DUV laser pulses, has been proposed and demonstrated so far.* In this study, a DUV nonlinear autocorrelator based on the proposed method was developed to measure the pulse duration of the DUV photocathode driving laser. As the result of measurement, the pulse duration was evaluated as 5.8±0.2 ps (FWHM). The principle of this method, experimental setup and measured results will be presented. * H. Zen et al., Proc. of FEL2014, pp.828-831 (2015). H. Zen et al., Proc. of IPAC2016, pp.754-756 (2016). * C. Homann et al., Applied Physics B 104, 783 (2011).
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2017-WEP014
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Paper

Title

Page

Present Status of Infrared FEL Facility at Kyoto University

162

H. Zen, T. Kii, S. Krainara, K. Masuda, H. Ohgaki, J. Okumura, S. Suphakul, S. Tagiri, K. Torgasin
Kyoto University, Kyoto, Japan

A mid-infrared free electron laser (FEL) named KU-FEL has been developed for promoting energy-related research at the Institute of Advanced Energy, Kyoto University.* KU-FEL can cover the wavelength range from 3.6 to 23 micrometers and is routinely operated for internal and external user experiments. Recently a THz Coherent Undulator Radiation (CUR) source using a photocathode RF gun has been developed as an extension of the facility.* As the result of commissioning the experiment, it was confirmed that the CUR source can cover the frequency range from 160 to 550 GHz. Present status of these infrared light sources will be presented.
* H. Zen et al., Physics Procedia 84, pp.47-53 (2016).

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2017-MOP050

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEP014

Pulse Duration Measurement of Pico-second DUV Photocathode Driving Laser by Autocorrelation Technique Using Two-Photon Absorption in Bulk Material

447

H. Zen, T. Kii, K. Masuda, T. Nakajima, H. Ohgaki
Kyoto University, Kyoto, Japan

A multi-bunch, pico-second DUV photocathode drive laser system has been developed for photocathode operation of mid-infrared free electron laser facility, KU-FEL.* By using the laser, KU-FEL has already succeeded in first lasing under the photocathode operation.** The pulse duration of the photocathode driving laser is a quite important parameter because it determines the initial electron pulse duration on the cathode surface. However, the pulse duration of the photocathode driving laser had not been characterized. A very convenient pulse duration measurement method utilizing two-photon absorption in bulk material, which can be used for DUV laser pulses, has been proposed and demonstrated so far.*** In this study, a DUV nonlinear autocorrelator based on the proposed method was developed to measure the pulse duration of the DUV photocathode driving laser. As the result of measurement, the pulse duration was evaluated as 5.8±0.2 ps (FWHM). The principle of this method, experimental setup and measured results will be presented.
* H. Zen et al., Proc. of FEL2014, pp.828-831 (2015).
** H. Zen et al., Proc. of IPAC2016, pp.754-756 (2016).
*** C. Homann et al., Applied Physics B 104, 783 (2011).

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-FEL2017-WEP014

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)