Brillouin Scattering and Synchrotron XRay Measurements

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Brillouin Scattering and Synchrotron X-Ray
Measurements at GSECARS, Advanced Photon Source
Simultaneous Measurements of Sound Velocities
and Density
A COMPRES Infrastructure Development
Project June 2005 Annual Meeting Status
Jay D Bass1 Stanislav V. Sinogeikin1 Vitali B.
Prakapenka2 Dmitry L Lakshtanov1 Carmen
Sanchez-Valle Guoyin Shen2 Mark Rivers2 1
Geology Dept, University of Illinois,
Urbana-Champaign, Urbana IL 61801 2 GSECARS,
University of Chicago, Chicago IL
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• Goals and motivations for building a Brillouin
  system at BMD-13
• Simultaneous measurements of
• Density by x-ray diffraction
• Sound velocities by Brillouin scattering
• Determination of an absolute pressure scales.
• The equation of state and velocities as a
  function of pressure could be determined without
  resort to a secondary pressure standard.
• Velocity-density measurements under a wide range
  of P-T conditions.
• High-T-P EOS parameters of materials (single
  crystal elastic constants, velocities, adiabatic
  and isothermal bulk moduli, shear modulus, and
  their P-T derivatives thermal expansion and
  Gruneisen parameter as a function of P and T)
• A central Brillouin facility, open to the entire
  community and not widely available elsewhere
  (except in a few specialized labs).

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Interpretation of global seismic information
Japan
Central America
Izu Bonin
Indonesia
Earths Surface
Fiji-Tonga
CMB 2890 km depth
(Kárason and Van der Hilst, AGU Monograph, 2000)
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Brillouin spectroscopy
obtain sound velocities (Vi VP or VS)
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• Key design considerations
• User-friendly possible to operate without being
  an expert.
• Quick setup and break-down of Brillouin
  experiments
• Fast and reliable alignment procedure, requiring
  minimum setup time.
• Complete remote control (of optics and
  electronics, data collection, outside the hutch
• Compatible with both powder and single crystal
  diffraction techniques
• Different scattering geometries 50, 80, 180
  degrees.
• Compact ( limited space in beamline station)
• Does not interfere with the other experimental
  techniques on the beamline
• Satisfy all laser safety requirements for Class
  IV laser

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• Timeline
• 2002-2004. Ordering equipment (e.g. Fabry-Perrot
  interferometer).
• Detailed design of the Brillouin system.
• Building up prototype at UIUC
• Testing , making blueprints, machining parts
  that could not be purchased.
• September 2004. Installing a second level table
  at BMD-13. Installing Fabry- Perot
  interferometer in BMD-13.
• October 2004. Installing most optical components
  at BMD-13.
• January 2005. Installing laser and permanent
  translation stages. Collecting the first
  Brillouin spectrum of standard MgO single crystal
  on Jan 16, 2005.
• February 2005. Commissioning. First measurements
  in DAC single crystal-NaCl to 30 GPa, single
  crystal MgO to 25 GPa polycrystalline B2-NaCl to
  53 GPa.
• Summer and fall 2005. Installation of additional
  components. Simultaneous high-T high-P
  measurements. Preparation for general users.
• 2006. Open for general users.

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Building The Prototype System at U Illinois
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Building prototype system in Urbana
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BMD-13 hutch before installation of the Brillouin
system
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Schematic diagram and photographs of the
Brillouin system installed at sector 13-BMD at APS
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Complete Brillouin system combined with X-ray
diffraction hardware
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Schematic diagram of the Brillouin system
installed at sector 13-BMd at APS
(Upper level)
Permanent optical elements M - mirror L - lens
BS - beam splitter PR - dispersion prism R -
retroreflector SF - spatial filter PMT -
photo-multiplier tube. Laser beam / image
conditioning elements (controllable from outside
the hatch, blue boxes) SSh - safety laser
shutter PRot - polarization rotator LDp - laser
beam depolarizer ICP - intensity control
polarized for stalilization beam IBS imaging
beam splitter CF - color filter NDF - neutral
density filter. Observation / feedback elements
(red boxes) PD - photodiode VC - video camera
MVC - microscope with video camera. Beam / image
alignment elements (yellow boxes) ID - iris
diaphragm ABBS - alignment beam beamsplitter
RBS - retroreflecting beamsplitter
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Schematic diagram of the Brillouin system
installed at sector 13-BMd at APS
(Lower level)
Motorized translation components (controllable
from outside the hatch, blue boxes) HMTS -
horizontal motorized translation stage VMTS -
vertical motorized translation stage MLFA -
motorized laser focusing assembly MSCA -
motorized signal collecting assembly SPOA -
sample positioning and orientation assembly
SL-LB - sample light / light block. Observation /
feedback elements (red boxes) VC - video camera
BT - beam target. X-ray components MAR - MAR
Imaging plate XBS - X-ray beam stop CS -
cleanup slit.
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X-ray and Brillouin control area for BMD-13
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Computer interface for controlling X-ray and
Brillouin optics and electronics
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Schematic view of simultaneous Brillouin
scattering and X-ray diffraction in DAC
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Simultaneous X-ray and Brillouin experiments
performed in BMD-13 in February 2005

• NaCl in B1 phase to 30 GPa.
• MgO to 25 GPa.
• Aggregate acoustic velocities, elastic moduli and
  equation of state of polycrystalline NaCl in B2
  phase to 53 GPa.
• In all absolute pressure scale experiments gold
  ruby ( platinum powdered NaCl) were added to
  experimental charges to cross calibrate these
  pressure standards against absolute equations of
  state of NaCl and MgO

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Single crystal NaCl (B1) at 30 GPa (left) and
polycrystalline NaCl (B2) at 53 GPa (right) in
DAC in Nepressure medium
AuPtNaCl
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MgO in MEW pressure medium. Typical DAC loading
for absolute pressure scale measurements.
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Single crystal X-ray diffraction and calibration
Brillouin spectrum of MgO at ambient pressure
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X-ray image and Brillouin spectrum of
polycrystalline NaCl in B2 structure collected
simultaneously at 35 GPa
NaCl Vp
Diamond Vs
NaCl Vs
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X-ray image and Brillouin spectrum of
single-crystal NaCl (B1) in Ne at 26 GPa
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Brillouin spectrum of single crystal MgO in 100
direction in a Diamond anvil cell at 4 GPa.
Collection time is 3.3 min.
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Acknowledgments

• COMPRES
• Jennifer Jackson
• Dave Mao
• J Shu