j. b. hastings [email protected] lusi doe review july 23, 2007 x-ray optics 1 x-ray optics j. b....
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J. B. [email protected]
LUSI DOE Review July 23, 2007X-ray Optics 1
X-ray Optics J. B. Hastings
X-ray Optics J. B. Hastings
Beam definitionAttenuatorsSlitsPulse picker
FocusingBe lensKirkpatrick-Baez Mirror systems
Diffractive opticsMonochromatorPulse compressorSplit and delay
Summary
Beam definitionAttenuatorsSlitsPulse picker
FocusingBe lensKirkpatrick-Baez Mirror systems
Diffractive opticsMonochromatorPulse compressorSplit and delay
Summary
J. B. [email protected]
LUSI DOE Review July 23, 2007X-ray Optics 2
6
1 24 5
1 SXR Imag
2 AMOS (LCLS)
3 XR pump-probe Full instrument
4 XPCS Full instrument
5 CXI Full instrument
6 HEDS
1 SXR Imag
2 AMOS (LCLS)
3 XR pump-probe Full instrument
4 XPCS Full instrument
5 CXI Full instrument
6 HEDS
LCLSLUSI
HEDS (NNSA)
Offset MonochromatorExp. ChamberDetector
Beam Transport
LUSI schematicLUSI schematic
XPP
3
XCS CXI
J. B. [email protected]
LUSI DOE Review July 23, 2007X-ray Optics 4
AttenuatorsAttenuatorsXCSXPPCXI
AttenuatorsVariable, up to 10 6 reductionHigh damage threshold (Be or B4C)
AttenuatorsVariable, up to 10 6 reductionHigh damage threshold (Be or B4C)
J. B. [email protected]
LUSI DOE Review July 23, 2007X-ray Optics 5
Slits SystemSlits SystemXCSXPPCXI
Slit systemsVariable horizontal and vertical gap from 5 μm – 5 mmCan withstand full LCLS flux – unfocusedMinimize background scatter from blades
Slit systemsVariable horizontal and vertical gap from 5 μm – 5 mmCan withstand full LCLS flux – unfocusedMinimize background scatter from blades
B. Lengeler et al., J. Synchrotron Rad., 6, 1153-1167 (1999).
J. B. [email protected]
LUSI DOE Review July 23, 2007X-ray Optics 6
Pulse PickerPulse PickerXCSXPPCXI
Pulse pickerPermit LCLS operation at 120 hzSingle pulses. Useful for samples supported on substratesReduced rate ex. 10 hz operationHigh damage thresholdUse rotating discs, concept already in use at ESRF
Pulse pickerPermit LCLS operation at 120 hzSingle pulses. Useful for samples supported on substratesReduced rate ex. 10 hz operationHigh damage thresholdUse rotating discs, concept already in use at ESRF
J. B. [email protected]
LUSI DOE Review July 23, 2007X-ray Optics 7
Be Focusing LensesBe Focusing LensesXCSXPPCXI
Beryllium CRL> 40% throughput
Positioning resolution and repeatability to 1 µmZ translation to vary spot size
Beryllium CRL> 40% throughput
Positioning resolution and repeatability to 1 µmZ translation to vary spot size
J. B. [email protected]
LUSI DOE Review July 23, 2007X-ray Optics 9
KB focusing mirrorsKB focusing mirrors
Mirror system (1 µm and 0.1 µm KB)
KB mirrors have produced 50 nm focuses of SR (Yamauchi et al., SRI 2006).Bent plane mirrors – or pre-figured Achromatic focusing.Use B4C as coating
Damage resistantGood reflectivity
J. B. [email protected]
LUSI DOE Review July 23, 2007X-ray Optics 10
KB Pair for 0.1 μm focusGrazing angle 0.2 DegB4C coatingHorz. Mirror 20 cmVert. Mirror 10 cmFocal spot size (FWHM in microns)
Horz: 0.097Vert: 0.083
J. B. [email protected]
LUSI DOE Review July 23, 2007X-ray Optics 11
LLNL has state-of-the-art surface metrology for the figure, mid- and high spatial frequency ranges
LLNL has state-of-the-art surface metrology for the figure, mid- and high spatial frequency ranges
10-2
103
108
1013
1018
10-8 10-6 10-4 10-2 100
diamond-turned Alpolyimide on Al, ML-coated
Frequency (nm-1)
PSD
(nm
4 )Slope error = 100 rad rms
= 2.7 Ǻ rms
= 17.6 Ǻ rms
AFM
Diamond-turned Aluminum surface, after polyimide and Mo/Si multilayer coating
Polyimide smoothes high spatial frequency roughness, including 10 m-range diamond turning marks
180 m
14
0
m
Measurements obtained with a Zygo New ViewTM optical profiling microscope operated at 40objective lens magnification
Diamond-turned Aluminum surface, as-received from manufacturer
100 nm
-200 nm
0 nm
Visible light interferometry results from multilayer-coated, diamond-turned condenser mirror
Height map Slope map
R. Soufli, E. Spiller, M. A. Schmidt, J. C. Robinson, S. L. Baker, S. Ratti, M. A. Johnson, E. M. Gullikson, Opt. Eng. 43(12), 3089-3095 (2004).
J. B. [email protected]
LUSI DOE Review July 23, 2007X-ray Optics 12
The LLNL DC-magnetron sputtering system can fit multiple large-area substrates in a single deposition
The LLNL DC-magnetron sputtering system can fit multiple large-area substrates in a single deposition
4-mirror and 2-mirror EUV cameras have been multilayer-coated in a single deposition run, achieving optic-to-optic wavelength matching within 1 = 0.010 nm
Underneath view of LLNL chamber lid with 5 sputtering targets
R. Soufli, E. Spiller, M. A. Schmidt, J. C. Davidson, R. F. Grabner, E. M. Gullikson, B. B. Kaufmann, S. L. Baker, H. N. Chapman, R. M. Hudyma, J. S. Taylor, C. C. Walton, C. Montcalm, and J. A. Folta, Proc. SPIE 4343, 51-59 (2001).
J. B. [email protected]
LUSI DOE Review July 23, 2007X-ray Optics 13
Stress and roughness vs. pressureStress and roughness vs. pressure
Lower pressure films reduce roughnessAlso increase stressCurves shift upwards as thickness grows
Favor thinner films grown at higher pressures
Higher micro-roughness, minimize risk of delamination
-2000
-1500
-1000
-500
0
500
1000
0 2 4 6 8 10 12 14 16 18 20
1
10
roughness
stress
dB
4C= 542- 565 Å
Ar sputtering pressure (mTorr)
Str
ess
(MP
a)
Rou
ghn
ess
(Å r
ms)
J. B. [email protected]
LUSI DOE Review July 23, 2007X-ray Optics 14
Offset MonochromatorOffset MonochromatorXCSXPPCXI
Parameter Value
Energy Range 6 – 24 keV
Horizontal Offset 600 mm
Scattering Angle 90 - 500
Accuracy 0.02 arcsec
χ Accuracy 4 arcsec
Double Crystal Offset monochromator Increase longitudinal coherence length (narrow X-ray spectrum)Multiplexes LCLS beam
Double Crystal Offset monochromator Increase longitudinal coherence length (narrow X-ray spectrum)Multiplexes LCLS beam
J. B. [email protected]
LUSI DOE Review July 23, 2007X-ray Optics 15
Offset MonochromatorOffset Monochromator
Double Crystal Offset monochromator for 2 µm Si (111) @ 1.5 Å
85% transmission ,2.5% - Mono beam, 1.3% - Diagnostics beam
Double Crystal Offset monochromator for 2 µm Si (111) @ 1.5 Å
85% transmission ,2.5% - Mono beam, 1.3% - Diagnostics beam
Scattering Angles (2 theta)
1.5 Å 0.5 Å
Silicon
11127.6° 9.1°
Silicon
22045.8° 14.9°
Diamond 111
42.5° 13.9°
Diamond 220
- 22.8°
J. B. [email protected]
LUSI DOE Review July 23, 2007X-ray Optics 16
Pulse CompressorPulse CompressorXCSXPPCXI
λ(nm)
d(nm)
θB b Sin βH
(mm)Δλ/λ(%)
0.15 2.0 2.1º +1 0.03 2600 0.5%
Parameters for a Laue case pulse compressor for the LCLS.
J. B. [email protected]
LUSI DOE Review July 23, 2007X-ray Optics 17
Split and DelaySplit and DelayXCSXPPCXI
Provided by DESY/SLAC MoU Prototype existing 1st Commissioning May 2007 pulse duration < delay < 3 ns
based on Si (511) with 2θ = 90º
E=8.389 keV
Provided by DESY/SLAC MoU Prototype existing 1st Commissioning May 2007 pulse duration < delay < 3 ns
based on Si (511) with 2θ = 90º
E=8.389 keV
J. B. [email protected]
LUSI DOE Review July 23, 2007X-ray Optics 18
SummarySummary
Optical components are conceptually the same as those for SR experiments: slits, attenuators, double crystal monochromators, refractive lens, KB focusingOptical components are in general not beyond state of the artCharacteristics of the LCLS beam demand extreme precision and damage tolerance: sub-micro radian rotations, B4C coatingsMultiplexing capability relies on thin Si or perfect diamond crystals