General Information

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Nd:YAG Laser

The Nd:YAG laser is located in a class 1000 clean room (the YAG Room) near the electron gun end of the ATF accelerator. The clean area also includes a separate laser laboratory area for laser development projects.Next to the YAG Room is the "Gun Hutch", containing UV optics for control of the light on the photocathode of the gun.The Nd:YAg laser is operated in a power amplifier mode, giving it a unique Pulse Train Mode. For certain experiments, like the FEL Oscillator Experiment, the YAG laser can deliver a pulse train with a pulse separation of 25 nanoseconds with a nearly arbitrary modulation.

Nd:YAG Drive Laser Functions

  • Generates primary facility user resources: -high brightness electron beam -high power CO2 laser pulses.
  • Timing: time structure & synchronization of above to one another and other facility equipment (i.e. delay generators, data acquisition, diagnostics).
  • Diagnostics pulses for experiments: e.g. Ion generation plasma density interferometry.
  • Cathode cleaning, detector characterization, optical timing fiducial, etc.

System Parameters

Energy (triple pulse mode)   Transverse Distribution  
UV on cathode 0-30 μJ X 1 pulse Range of beam size on cathode (0) 0.2-3 mm
IR to CO2 laser 10 mJ X 2 pulses Top-hat beam profile modulation (P-P) < 50%
Laser output, total IR 30 mJ    
IR to gun 7.5 mJ Repetition Rate 1.5, 3 Hz
Green 2.5 mJ    
UV 500 μJ Shot-to-shot stability (rms)  
    Timing < 0.2 ps
Energy (pulse train mode) IR ~100 mJ/20 pulses Energy < 0.8%
    Pointing (fraction of beam 0) < 0.3%
Pulse duration (FWHM)      
Oscillator IR 7 ps Drift (8 hour P-P)  
Amplified IR 14 ps Timing < 15 ps
Green 10 ps Energy < 5%
UV 8 ps Pointing (fraction of beam 0) < 1%

Facility-Laser Interaction

Nd:YAG Laser