1. E- source R&D update ILC source laser project Faraday rotation experiment
A. Brachmann
05/07/07
SLAC R&D meeting

2. Mode-locked pulse train (76 MHz)
05/07/07
SLAC R&D meeting

3. MIRA Power Mode of operation Power SLAC R&D meeting
cw alignment cavity
0.93 W
Main cavity
0.8 W
Mode-locked operation
0.45 W
(76 MHz, 5.9 nJ)
05/07/07
SLAC R&D meeting

4. MIRA wavelength tuning curve
~ 760 nm
To get peak at 780 nm we need new cavity optics
05/07/07
SLAC R&D meeting

5. MIRA efficiency
05/07/07
SLAC R&D meeting

6. MIRA ML spectrum SLAC R&D meeting FWHM = 2.8 nm = 760 nm
BW [Hz] = (FWHM*3*108) / 2
T = 0.44 / BW = 300 fs
Stretching by a factor of ~ 3000
to obtain 1 ns
05/07/07
SLAC R&D meeting

7. Extend cavity to reduce repetition rate and increase peak power
Near term plans
Extend cavity to reduce repetition rate and increase peak power
Measure pulse width (Auto-correlator)
Pulse stretching
3 MHz train generation using fast Pockel’s cell
05/07/07
SLAC R&D meeting

8. Faraday Rotation Experiment
Measures Depolarization Dynamics
Depolarization occurs during transport through cathode material
Understanding depolarization allows design of optimized photocathodes
05/07/07
SLAC R&D meeting

9. Faraday Rotation Experiment Schematic
05/07/07
SLAC R&D meeting

10. Depolarization Dynamics Measurement
General shape,
Not a measurement!
05/07/07
SLAC R&D meeting

11. Faraday Rotation Experiment Status
Ar – Ion laser 20 + years old
Converted from multi line to single line operation
Evaluating and improving stability of Ar – ion laser
Experiment set up complete
Detector setup optimization options:
Low noise photodiodes
CCD camera (loan of ICCD from SPPS)
05/07/07
SLAC R&D meeting