EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis EUROFEL DS3-DS4 TASK meeting...
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Transcript of EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis EUROFEL DS3-DS4 TASK meeting...
EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis
EUROFEL DS3-DS4 TASK meeting
Proposed synchronization schemes for 4GLS: impact on EUROFEL DS3
Mario Ferianis - Sincrotrone Trieste, Italy
CEA, Saclay 16-17 May 2005
• Synchronization issues• Proposed schemes
• Workplan for EUROFEL DS3
EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis
Synchronization issues
• In 3GLS, synchronization is used for– Injector: tens of ps s-band / 10 30ps
– Injection and extraction systems: 100s of ps
– Bunch diagnostics and feedback systems: few ps
– Time-resolved experiments (laser to h synch.): few ps
• Being the bunch length tB40psFWHM, typically the required
jitter is at the few psRMS level
• In 4GLS, synchronization is a key feature due to:– sub-ps bunch length, achievable in single pass accelerator
– extensive adoption of fs lasers, both embedded in the radiation production process and foreseen for time resolved experiments
• Minimum required synch. : <10fs level (i.e. seeding laser)
EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis
Synchronization issues:some thoughts from my “bulleted list”, 01/2004
• The synchronization (after the greek verb: =to be/to happen at the same time) of a system can be defined as its property of sharing a common time reference and distributed among its different sub-systems. Synchronous sub-systems, therefore, can operate at fixed relative time instants. The term “timing system” is frequently used as synonymous of synchronization system.
• The preservation of the synchronization over long terms is called stability: a synchronous system is also stable when its synchronization is kept over long times, order of magnitude larger than the “event”.
• Femto-second x-ray Light Source test stands have already proven to generate sub-picosecond (10-14s) x-ray pulses, at repetion rates of few Hertz (10-2s), to be delivered during User Shifts of many hours (104s). Therefore, the synchronization of a femto-second x-ray Light Source has to deal with 18 order of magnitude, which calls for state of the art solutions.
EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis
Synchronization & Stability
• Do we really need both fs synchronization & stability ?
• During the 1st FERMI User Workshop, there have been some discussions about it…turned out that:“each LINAC shot (FEL pulse) is like one experiment”
• So, what Users are really needing is fs synchronization, but relative to events within one machine cycle: tREP=20ms (50Hz) for FERMI
• What do they really care is that pump pulses are stable (<10fsRMS )
w.r.t. probe pulses, considered as associated pairs!
• Furthermore, both the physical phenomena and the related data taking techniques on fs experiments complete well before milliseconds repetition period
EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis
Synchronization issues:sequence of synchronous events
Optical Reference laser pulse
PC laser pulse on cathode
Phase of accelerating voltage
Laser Heater pulse
Seed Laser pulse
Cross-correlator Laser pulse
Probe Laser pulse
Pump Laser pulse
ABSOLUTE STABILITY
JITTER JITTER
ns range
ms range
EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis
Proposed schemes:a general layout for a 4GLS synchronization system
0.3 nm 0.1 nm
UV Hall X-ray Hall
Nanometer Hall
SC Linac4 GeV2 GeV1 GeV
1 nm
0.3 nm
100 nm
30 nm
10 nm
10 nm
3 nm
1 nm
Master oscillator
Pump laser
Pump laser
Seed laser
Seed laser
Seed laser
Pump laser
Fiber link synchronization
Injector laser
Undulators
Undulators
Undulators
Future upgrade to 0.1 nm at 8 GeV
SC Linac
MIT Optics & Quantum Electronics Group
04/11/23W.S. Graves,MIT Bates Laboratory
EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis
Synchronization issues: adopted optical techniques
EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis
EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis
Synchronization issues:phase noise representation
f0=carrier
Sidebands
Amplitude vs. carrier
Amp.[dBc/Hz]
“Phase Noise and Jitter”,N. Roberts, ZARLINK semicond.EE Design, July 14 2003
EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis
Synchronization issues:phase noise to jitter conversion
1/fm0
White frequency:uncorrelated fluctuations of the osc. period;thermal noise
Flickernoise
“Phase Noise and Jitter”,N. Roberts, ZARLINK semicond.EE Design, July 14 2003
EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis
Synchronization issues
“Phase Noise and Jitter”,N. Roberts, ZARLINK semicond.EE Design, July 14 2003
EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis
Synchronization issues
“Phase Noise and Jitter”,N. Roberts, ZARLINK semicond.EE Design, July 14 2003
10dBc / 3 decades:L(f)=1/SQRT(f3)
EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis
SSB Phase noise measurement:effects due to Instrument powering cofiguration:
ac vs. battery source
EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis
Proposal for fs synchronization:RLE @ MIT + DESY
EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis
Measured fiber laser performanceF.O. Ilday et al. “Laser Technology for X-ray FELs: fs synchronization
…” presented at Erl 2005 workshop, JLAB
EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis
Synchronization issues: stabilized FO link Lasers and RF-Timing, Franz X. Kaertner, RLE MIT
CrossCorrelatorFiber
ML - Laser
PZT
Fixed Length L
Far end local end
EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis
Proposed schemes:Optical to RF conversion
RF synchronous to optical pulses
EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis
Proposed schemes: Optical to RF conversion
EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis
Locking of two fiber lasersF.O. Ilday et al. “Laser Technology for X-ray FELs: fs
synchronization …” presented at Erl 2005 workshop, JLAB
Reference laser:LOCAL
Second laser:REMOTE
Long FO link
EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis
Stabilization of reference signal distribution25GHz, 1km of fiber, 15 hour test
EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis
EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis
Stabilization of FO link: LBL proposal R. Wilcox, J. W. Staples LBL, R. Holzwarth, Menlo Systems “Optical Synchronization Systems for fs x-ray sources” PAC ‘05
far end
close end
EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis
R. Wilcox, J. W. Staples LBL, R. Holzwarth, Menlo Systems “Optical Synchronization Systems for fs x-ray sources” PAC ‘05
Proof of principle of Mach-Zender interferometer:with 40m of fiber in one arm showing 100s fs of jitter, it has been reduced to 0.85fs!
EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis
Stabilization of FO link: LBL proposal R. Wilcox, J. W. Staples LBL, R. Holzwarth, Menlo Systems “Optical Synchronization Systems for fs x-ray sources” PAC ‘05
since heterodyning preserves phases,phase shifts in the 110MHz is reflectedin identical phase shift in the optical signal: 1deg @110MHz==1 deg optical 0.014fs!!!
EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis
Multiple frequencies vs. Pulse train
• Multiple frequencies*
– Lower peak optical power, below non-linear effects threshold (Brillouin, Raman)
– With RF beat detection, optical to RF conversion efficiency is maximized, opposed to extraction of a high harmonic from a pulse train (losses in BP filter)
– Phase detection is measuring very high frequency beat between optical waves rather than at lower waves
• Pulse train
– No need to delivery at the far end the 110MHz signal
– Can distribute either 100MHz or 3GHz signal (direct O/E conversion for the RF plants)
– Can be used as seed for other lasers and as ref pulse in diagnostics * R. Wilcox, J. W. Staples LBL, R. Holzwarth, Menlo Systems “Optical Synchronization Systems for fs x-ray sources” PAC ‘05
EUROFEL DS3-DS4 TASK meeting CEA - Saclay, 16-17 MAY 2005 M. Ferianis
Workplan for EUROFEL DS3:demonstration of the Optical Clock
REF.osc.
Fiberlaser
O/EConv.
Remote fs laser
Phase
detect
Stabilised Fiber links: star configurationL=300m
Phasenoise
Cross-correlat
e
Electrical signalOptical in fiberOptical in air
RF: 100MHz or-wave: 10GHz
fPULSE