Xray PumpProbe Workshop

1
X-ray Pump-Probe Workshop

• David Fritz
• (for the XPP and LUSI Team)
• XPP Instrument Scientist
• October 21, 2009

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The XPP Team
XPP Science Group
Marco Cammarata
XPP Engineering Group (led by J. Langton)
J. Brian Langton
Jim Defever
JimDeLor
And many more!
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LCLS Parameters
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XPP Instrument Overview
XPP Control Room
XPP Endstation
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XPP Instrument Overview
Photon Shutter
Intensity Monitor
Slits
Profile Monitor
Intensity Monitor
Slits
Focusing Lenses
Attenuators
Pulse Picker
Mirrors
Slits
Intensity Monitor
Profile Monitor
Sample Goniometer
Detector Mover
Profile Monitor
Intensity Monitor
Photon Shutter
6
XPP Instrument Overview
Detector Mover
Ultrafast Laser
Detector
Diagnostics
Sample Goniometer
X-ray Optics Diagnostics
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Intensity Position Monitor
Photon Shutter
Intensity Monitor
Slits
Profile Monitor
Intensity Monitor
Slits
Focusing Lenses
Attenuators
Pulse Picker
Mirrors

• Purpose
• Per-pulse normalization of experimental signals
• High-resolution beam position monitoring
• Specifications
• Highly transmissive (lt 5 loss)
• Relative accuracy lt 0.1
• Dynamic range 1000
• Per-pulse op. at 120 Hz

Slits
Intensity Monitor
Profile Monitor
Sample Goniometer
Detector Mover
Profile Monitor
Intensity Monitor
Photon Shutter
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Slits
Photon Shutter
Intensity Monitor
Slits
Profile Monitor
Intensity Monitor
Slits
Focusing Lenses
Attenuators
Pulse Picker
Mirrors
Slits

• Purpose
• Defines the beam size position
• Clean up scatterings (halo) around beam perimeter
• Specifications
• Can withstand full LCLS flux unfocused
• Minimize background scatter from blades
• 0.5 µm accuracy

Intensity Monitor
Profile Monitor
Sample Goniometer
Detector Mover
Profile Monitor
Intensity Monitor
Photon Shutter
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Profile - Intensity Monitor
Photon Shutter
Intensity Monitor
Slits
Profile Monitor
Intensity Monitor
Slits
Focusing Lenses
Attenuators
Pulse Picker
Mirrors
Slits

• Purpose
• Coarse beam alignment/monitoring Coarse/fine
  beam profile
• Specifications
• Destructive Retractable
• At 100 mm resolution - 24x24 mm2 field of view
• At 8 mm resolution - 2x2 mm2 field of view
• Capable of per-pulse op. _at_ 120 Hz

Intensity Monitor
Profile Monitor
Sample Goniometer
Detector Mover
Profile Monitor
Intensity Monitor
Photon Shutter
10
X-ray Focusing Lenses
Photon Shutter
Intensity Monitor
Slits
Profile Monitor
Intensity Monitor
Slits
Focusing Lenses
Attenuators
Pulse Picker
Mirrors
Slits

• X-ray Focusing Lens System
• Down to 2 µm beam waist
• Variable spot size from 2-10 µm and 40-60 µm when
  working out of focus
• Can withstand full LCLS flux
• Variable lens to sample distance

Intensity Monitor
Profile Monitor
Sample Goniometer
Detector Mover
Profile Monitor
Intensity Monitor
B. Lengeler et al., J. Synchrotron Rad., 6,
1153-1167 (1999).
Photon Shutter
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X-ray Focusing Lenses
Photon Shutter
Intensity Monitor
Slits
Profile Monitor
Intensity Monitor
Slits
Focusing Lenses
Attenuators
Pulse Picker
Mirrors
Slits
Intensity Monitor
Profile Monitor
Sample Goniometer
Detector Mover
Profile Monitor
Intensity Monitor
Photon Shutter
12
Attenuator - Pulse Picker
Photon Shutter
Intensity Monitor
Slits
Profile Monitor
Intensity Monitor
Slits
Focusing Lenses
Attenuators
Pulse Picker
Mirrors
Slits
Intensity Monitor

• LUSI Attenuator\Pulse Picker System
• Excellent Optical Quality
• gt 3 steps per decade of attenuation above 6 keV
• gt 1012 attenuation lt 17 keV
• Isolate 3rd harmonic from fundamental
• Tailor rep rate up to 10 Hz

Profile Monitor
Sample Goniometer
Detector Mover
Profile Monitor
Intensity Monitor
Photon Shutter
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Attenuator - Pulse Picker
Photon Shutter
Intensity Monitor
Slits
Profile Monitor
Intensity Monitor
Slits
Focusing Lenses
Attenuators
Pulse Picker
Mirrors
Slits
Intensity Monitor
Profile Monitor
Sample Goniometer
Detector Mover
Profile Monitor
Intensity Monitor
Photon Shutter
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Attenuator - Pulse Picker
Photon Shutter
Intensity Monitor
Slits
Profile Monitor
Intensity Monitor
Slits
Focusing Lenses
Attenuators
Pulse Picker
Mirrors
Slits
Intensity Monitor
1.25
Profile Monitor
Sample Goniometer
Detector Mover
Profile Monitor
Intensity Monitor
Photon Shutter
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Attenuator - Pulse Picker
Photon Shutter
Intensity Monitor
Slits
Profile Monitor
Intensity Monitor
Slits
Focusing Lenses
Attenuators
Pulse Picker
Mirrors
Slits
Intensity Monitor
Profile Monitor
Sample Goniometer
Detector Mover
Profile Monitor
Intensity Monitor
Photon Shutter
16
Harmonic Rejection Mirrors
Y AXIS STAGE
Y
Photon Shutter
ROTARY STAGE
Intensity Monitor
BEAM DIRECTION
Slits
Y STAGE MOUNT
Profile Monitor
SILICON MIRROR
Intensity Monitor
Slits
KINEMATIC MOUNT
Focusing Lenses
Attenuators
Pulse Picker
X
Z
Mirrors
2X X AXIS STAGE
Slits
A
Intensity Monitor

• Harmonic Rejection Mirror System
• Good optical quality
• Si single crystal
• 300 mm
• No prefigure, no bender

Profile Monitor
B
Sample Goniometer
Detector Mover
C
Profile Monitor
Intensity Monitor
Photon Shutter
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Harmonic Rejection Mirrors
Photon Shutter
Intensity Monitor
Slits
Profile Monitor
Intensity Monitor
Slits
Focusing Lenses
Attenuators
Pulse Picker
Mirrors
Slits
Intensity Monitor
Profile Monitor
Sample Goniometer
Detector Mover
Profile Monitor
Intensity Monitor
Photon Shutter
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Harmonic Rejection Mirrors
Photon Shutter
Intensity Monitor
Slits
Profile Monitor
Intensity Monitor
Slits
Focusing Lenses
Attenuators
Pulse Picker
Mirrors
Slits
Intensity Monitor
Profile Monitor
Sample Goniometer
Detector Mover
Profile Monitor
Intensity Monitor
Photon Shutter
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XPP Sample Goniometer
Photon Shutter

• Tilt Platform
• Capable of orienting large sample environments (
  50 kg)
• Open access to allow close proximity laser optics
• Operate in direct or future monochromatic beam
• 400 mm x 400 mm mounting surface
• 200 mm platform to center of rotation distance

Intensity Monitor
Slits
Profile Monitor
Intensity Monitor
Slits
Focusing Lenses
Attenuators
Pulse Picker
Mirrors
Slits
Intensity Monitor
Profile Monitor
Sample Goniometer
Detector Mover
Profile Monitor
Intensity Monitor
Photon Shutter
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XPP Sample Goniometer

• Kappa Goniometer
• Capable of orienting small samples ( 50 µm) over
  a wide range of reciprocal space
• Sphere of confusion lt 30µm
• Open access to allow close proximity laser optics
• Operate in direct or future monochromatic beam

Photon Shutter
Intensity Monitor
Slits
Profile Monitor
Intensity Monitor
Slits
Focusing Lenses
Attenuators
Pulse Picker
Mirrors
Slits
Intensity Monitor
Profile Monitor
Sample Goniometer
Detector Mover
Profile Monitor
Intensity Monitor
Photon Shutter
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XPP Sample Goniometer
Photon Shutter
Intensity Monitor
Slits
Profile Monitor
Intensity Monitor
Slits
Focusing Lenses
Attenuators
Pulse Picker
Mirrors
Slits

• Goniometer Base
• Large steel weldment
• Provisions for beamstop and camera mounting
• Leveling capability

Intensity Monitor
Profile Monitor
Sample Goniometer
Detector Mover
Profile Monitor
Intensity Monitor
Photon Shutter
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XPP Detector Mover

• Detector Mover
• 10 cm 100 cm sample to detector distance
• Repeatable position the XPP detector pixels to a
  fraction of the pixel size
• Definitively know the position of all detector
  pixels to a fraction of the pixel size
• Operate in both interaction points without
  interferences
• Remotely variable sample to detector distance
• Permit the sample goniometer to meet the motion
  requirements
• Decoupled from sample goniometer

Photon Shutter
Intensity Monitor
Slits
Profile Monitor
Intensity Monitor
Slits
Focusing Lenses
Attenuators
Pulse Picker
Mirrors
Slits
Intensity Monitor
Profile Monitor
Sample Goniometer
Detector Mover
Profile Monitor
Intensity Monitor
Photon Shutter
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XPP Detector Mover
Photon Shutter
Intensity Monitor
Slits
Profile Monitor
Intensity Monitor
Slits
Focusing Lenses
Attenuators
Pulse Picker
Mirrors
Slits
Intensity Monitor
Profile Monitor
Sample Goniometer
Detector Mover
Profile Monitor
Intensity Monitor
Photon Shutter
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XPP Detector Mover
Photon Shutter
Intensity Monitor
Slits
Profile Monitor
Intensity Monitor
Slits
Focusing Lenses
Attenuators
Pulse Picker
Mirrors
Slits
Intensity Monitor
Profile Monitor
Sample Goniometer
Detector Mover
Profile Monitor
Intensity Monitor
Photon Shutter
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XPP Detector Mover
Photon Shutter
Intensity Monitor
Slits
Profile Monitor
Intensity Monitor
Slits
Focusing Lenses
Attenuators
Pulse Picker
Mirrors
Slits
Intensity Monitor
Profile Monitor
Sample Goniometer
Detector Mover
Profile Monitor
Intensity Monitor
Photon Shutter
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XPP Detector Mover
Photon Shutter
Intensity Monitor
Slits
Profile Monitor
Intensity Monitor
Slits
Focusing Lenses
Attenuators
Pulse Picker
Mirrors
Slits
Intensity Monitor
Profile Monitor
Sample Goniometer
Detector Mover
Profile Monitor
Intensity Monitor
Photon Shutter
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XPP Detector

• XPP Detector System
• Developed at BNL
• High detector quantum efficiency
• Single photon sensitivity
• Large dynamic range gt103
• 104 photon dynamic range per pixel
• 120 Hz readout rate
• 1024 x 1024 square pixels
• Four 512 x 512 quadrants
• 90 µm pixel size

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Laser System

• XPP Laser System
• Will utilize and expand upon AMO laser system
• AMO Laser Requirements
• gt 3 mJ per pulse energy at sample (800 nm)
• lt 50 fs pulse duration
• 120 Hz
• lt 100 fs phase jitter to LCLS RF
• Multipass amplifier
• gt20 mJ per pulse energy (800 nm)
• lt 50 fs pulse duration
• 120 Hz
• Frequency conversion capability
• OPA
• Harmonic generation
• Temporal pulse shaping capability
• Diagnostics suite
• System designed such that a non-laser trained
  user can perform an XPP experiment
• Sufficient automation to control laser parameters
• Sufficient engineering controls to provide safe
  working environment

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Laser System
PM1
F1
Spectrometer
Csp
PM2
Oscope
Laser
Oscillator Controls
?/2-1
Laser Hall
F2
PMOsc
Hutch 2
PM4
PM3
C2
C5
M2
VEC
M1
?/2-2
L2
L1
?/2-3
Harmonics
C1
To Experiment
L4
M4
C4
M3
To Experiment
L3
L5
2?VEC
C3
AC
?/2-4
PM5
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Current Status
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Laser Tables
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X-ray Tables
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X-ray Tables
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Diagnostic Devices
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Detector Mover
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Synchronization
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Non-inherent Synchronization
Non-inherent Synchronization - Pump and probe
derived from different sources

• Inherent Synchronization
• - Pump and probe derived from same source

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Synchronizing the Linac
R. Akre
RF HUT
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Active Synchronization
SPPS
Error Signal sin (?rft) x sin(?Ltf)
cos (?rf-?Lt-f)-cos (?rf?Ltf)

• 60 fs integrated phase jitter has been achieved
  at the LCLS gun laser

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The Drift Problem
SPPS
???
LCLS
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LCLS Ultrafast Timing System
LBL Team
Russell Wilcox, Gang Huang, Larry Doolittle
seated, John Byrd, Alex Ratti and John Staples
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LCLS Ultrafast Timing System (2)
2km fiber
1530nm
55MHz
CW fiber laser
freq. shifter
output
ref. arm
f1
f1 110MHz
C2H2 freq. locker
110MHz beat
110MHz oscillator
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LCLS Ultrafast Timing System (3)
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LCLS RF Distribution Scheme (LBNL)
2km fiber
1530nm
55MHz
CW fiber laser
freq. shifter
output
ref. arm
f1
f1 110MHz
C2H2 freq. locker
110MHz beat
110MHz oscillator
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LCLS Ultrafast Timing System (4)
Out-of-loop results for installed 300m fiber
loop, 2856MHz. 17fs RMS over 11.5 hours. Short
term, 14fs RMS. Results submitted to OFC 2010
Proceedings
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LCLS Timing Cavity

• However, e-beam still jitters and drifts with
  respect to timing reference (gt50 fs rms short
  term jitter)
• This jitter will be measured with an electron
  beam timing cavity and each pulse will be time
  stamped

Joe Frisch
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LCLS Timing Cavity
Undulator Hall
Joe Frisch
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LCLS Timing Cavity
Noise (blue), drift (red) of a timing cavity and
correlation between two cavities (green)
Picoseconds
Preliminary results over 16 hours of operation -
Courtesy of Joe Frisch
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Phase Cavity Limitations at LCLS

• Limited by
• Ability to phase pump laser to the timing signal
• Distribute a stabilized timing signal
• Measure the timing of the electron bunch

• Only measures timing of electron bunch not of FEL
  directly

Cooperation Length Slippage Length
ltlt Bunch Duration
Different portions of the bunch can lase
Laser Lock
Time
Timing Distribution
Timing Cavity