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DOI:10.18429/JACoW-FEL2015-MOP036
Title Femtosecond Synchronization of 80-MHz Ti:Sapphire Photocathode Laser Oscillator with S-Band RF Oscillator
Authors
  • H. Yang, C. Jeon, K. Jung, J. Kim
    KAIST, Daejeon, Republic of Korea
  • H. Chung
    Korea University Sejong Campus, Sejong, Republic of Korea
  • B. Han, Y.U. Jeong
    KAERI, Daejon, Republic of Korea
Abstract Precision synchronization between lasers and RF sources in free-electron lasers (FELs) and ultrafast electron diffraction (UED) systems is becoming more important. There have been intense research and development toward femtosecond synchronization of lasers and RF sources in the last decade. Most of the previous approaches at large-scale FELs have used cw lasers or low-jitter mode-locked lasers at telecomm wavelength as the master oscillator and distributed the timing signals via stabilized fiber links. However, for smaller-scale FELs and UED, this approach may be a complex and high-cost method. In this work, we studied the possibility of using the commercial Ti:sapphire photocathode laser as the optical master oscillator as well. For its use in UED and FELs, we synchronized the 80-MHz Ti:sapphire photocathode laser oscillator to a 2.856-GHz RF source (used for RF-photogun) with 50-fs precision. Some interesting findings are following. First, intrinsic rms timing jitter of the used photocathode laser is 2.6 fs [10 kHz-10 MHz], which sets the fundamental limit in synchronization. Second, timing jitter in 100 Hz-1 kHz in photocathode laser is so severe (e.g., ~40 fs even feedback control is applied), so that it will require additional external-cavity control for achieving sub-10-fs precision. By addressing this issue, we are currently working toward 10-fs precision.
Paper download MOP036.PDF [0.371 MB / 2 pages]
Conference FEL2015, Daejeon, Republic of Korea
Series International Free Electron Laser Conference (37th)
Proceedings Link to full FEL2015 Proccedings
Session Poster Session
Date 24-Aug-15   15:00–17:00
Main Classification FEL Technology and HW: Electron Diagnostics, Timing, Synchronization, and Controls
Keywords laser, timing, detector, FEL, electron
Publisher JACoW, Geneva, Switzerland
Editors Heung-Sik Kang (PAL, Pohang, Republic of Korea); Dong Eon Kim (PAL, Pohang, Republic of Korea); Volker RW Schaa (GSI, Darmstadt, Germany);
ISBN 978-3-95450-134-2
Published December 2015
Copyright
Copyright © 2015 by JACoW, Geneva, Switzerland     CC-BY Creative Commons License
cc Creative Commons Attribution 3.0