ASAC Introduction
-
Upload
wiji-astuti -
Category
Documents
-
view
224 -
download
0
Transcript of ASAC Introduction
-
8/3/2019 ASAC Introduction
1/47
MIT X-ray Laser ProjectA true x-ray laser will have enormous impact
No x-ray source is coherentNo laser has much power for l < 30 nm
Murnane and Kapteyne produced l=31nm
light pulses with a nano-Joule per pulse
The number of photons per quantum state,
the photon degeneracy is less than 0.1
-
8/3/2019 ASAC Introduction
2/47
X-ray Lasers: Promise to be a comprehensive probe of all spatial and
temporal scales and resolutions relevant to condensed matter
Spatial Scales Temporal Scales
-
8/3/2019 ASAC Introduction
3/47
MIT X-ray Laser Project
Unique opportunity to integrate:
Accelerator technology
(MIT/Bates Lab)
Fast laser technology
(MIT Ultrafast Group)
-
8/3/2019 ASAC Introduction
4/47
Self-Amplified Spontaneous Emission (SASE)
SASE Radiation has full Transverse Coherence
-
8/3/2019 ASAC Introduction
5/47
-
8/3/2019 ASAC Introduction
6/47
-
8/3/2019 ASAC Introduction
7/47
APS DemonstratesSelf-Amplified Spontaneous Emission (SASE)
-
8/3/2019 ASAC Introduction
8/47
-
8/3/2019 ASAC Introduction
9/47
-
8/3/2019 ASAC Introduction
10/47
SASE Radiation is not Transform Limited
310/ =cle
NN
310/ el NNc
A SASE FEL is an amplifier of electron density modulations
-
8/3/2019 ASAC Introduction
11/47
SASE Radiation is Powerful, But Noisy
t (fs) Dw/w (%)
-
8/3/2019 ASAC Introduction
12/47
Seeding to Limit Fluctuations
-
8/3/2019 ASAC Introduction
13/47
-
8/3/2019 ASAC Introduction
14/47
Data from BNL DUV-FEL experiment
-
8/3/2019 ASAC Introduction
15/47
Seeded beam SASE beam
Output
wavelength
FEL param
rFEL
Dtmin (fs) at
max BW
DEmin (meV) at
1 ps FWHM
SASE Dtmin
(fs)
SASE DEmin
(meV)100 nm 9.e-3 20 2 100 110
10 nm 4.e-3 5 2 100 500
1 nm 1.5e-3 1 2 100 1900
0.1 nm 0.2e-3 0.8 2 100 2500
Bandwidth and Pulse Length
1
2f tD D
FELf fr
D=
Seeded beams limited only by
uncertainty principle and seed
properties.
SASE properties determinedby ebeam.
-
8/3/2019 ASAC Introduction
16/47
MIT X-ray Laser Project
Provide full transverse and longitudinal coherence get rid of the SASE noise
Provide wide spectrum coverage: 100 nm > l
-
8/3/2019 ASAC Introduction
17/47
MIT X-ray Laser Project
How to reach wavelengths below 1 nm?
Must get the shortest wavelength seeds
using High Harmonic Generation methods,--30nm available now, possible 10 nm or below
Then use cascaded High Gain
Harmonic Generation methods in FEL,--factors of >30 are possible
-
8/3/2019 ASAC Introduction
18/47
-4 -2 0 2 4Time, fs
x-ray harmonicemission=
=/
MIT Ultra-fast GroupHHG seeding methods
J. Fujimoto, H. Haus, E. Ippen, F. Kaertner
See current issue of Physics Today
-
8/3/2019 ASAC Introduction
19/47
High-Harmonic Generation
Noble Gas Jet (He, Ne, Ar, Kr)
100 mJ - 1 mJ@ 800 nm
XUV @ 3 30 nm
h = 10-8 - 10-5
Recombination
Propagation
-Wb
wXUV
Energy
t
x
tb
0
Laser electric field
Ionization
-
8/3/2019 ASAC Introduction
20/47
High Gain Harmonic Generation
Modulator is tuned tow0.
Electron beamdevelops energy
modulation at w0.
3rd harmonicbunching isoptimized inchicane.
Energy modulation is
converted to spatial
bunching in chicane
magnets.
Input seed at w0
overlaps electron
beam in energy
modulator undulator.
Electron beam radiates
coherently at w3 in long
radiator undulator.
Radiator is tuned to w3.
Method to reach short wavelength FEL output from longer
wavelength input seed laser.
-
8/3/2019 ASAC Introduction
21/47
Cascaded HGHG
Input
seed w01st stage 2nd stage 3rd stage
Output at 3w0
seeds 2nd stage
Output at 9w0
seeds 3rd stage
Final output
at 27w0
Number of stages and harmonic of each to be optimized during study.
Factor of 10 30 in wavelength is reasonable without additional
acceleration between stages.
Seed longer wavelength (100 10 nm) beamlines with ~200 nm harmonic
from synchronized Ti:Sapp laser.
Seed shorter wavelength (10 0.3 nm) beamlines with HHG pulses.
-
8/3/2019 ASAC Introduction
22/47
Laser System & SynchronizationHigh Harmonic
Generation
1 nJ 10 nJ
100 as 10 ps
1-20 kHz
@ 1 - 30 nm
Photo-Injector:
1-10 ps Pulses
1-10 mJ
1-20 kHz
@ 266 nm(conv. NLO)
Fiberlink + Synchronization
LINAC FELE-beam
~200 m
10 fsTiming Jitter
Output: Three highly synchronized pulse streamsE-beam, EUV 1 - 30 nm and @ 800 nm driver pulse
-
8/3/2019 ASAC Introduction
23/47
0.3 nm 0.1 nm
UV Hall X-ray Hall
Nanometer Hall
SC Linac
4 GeV2 GeV1 GeV
1 nm
0.3 nm
100 nm
30 nm
10 nm
10 nm
3 nm
1 nm
Main oscillator
Pump
laserPump
laser
Seed
laser
Seed
laser
Seed
laser
Pump
laser
Fiber link synchronization
Injector
laser
Undulators
Undulators
Undulators
Upgrade: 0.1 nm
at 8 GeV
SC Linac
MIT X-ray Laser Concept
-
8/3/2019 ASAC Introduction
24/47
to master oscillator for timing sync
Pump
lasersTi:Sapp + BBO = 200 nm seed
Ti:Sapp + HHG = 10-30 nm seed
Tune by OPA or harmonic number
10 nm
3 nm
1 nm
Direct seeded or cascaded
HGHG undulators
Nanometer Hall
Seed
lasers
Ti:Sapp + HHG = 10-30 nm seed
Tune by OPA or harmonic number
Cascaded HGHG undulators
Cascaded HGHG undulators
~20 m length
10 GW peak
~30 m length
4 GW peak
-
8/3/2019 ASAC Introduction
25/47
Pulse Structure (Quasi-CW)
SC Linac Pulse @1Hz 10% Duty Factor
0 500 1000 1500 2000 2500
Time (ms)
~90 Warm RF Gun Pulses 1 ms spacing
0 100
Time (ms)
RF Gun Pulse
-10 0 10 20Time (us)
0.1% Duty Factor
8 Pulses
8 Beamlines
~500 pC / Pulse
1 us spacing
-
8/3/2019 ASAC Introduction
26/47
Seeding for short pulse
0.2995 0.3 0.3005 0.3010
200
400
600
800
1000
Wavelength (nm)
Power(kW/bin)
0.2995 0.3 0.3005 0.3010
200
400
600
800
1000
Wavelength (nm)
Power(kW/bin)
Output time profile Time profile (log plot) Spectrum
0 10 20 30 40 5010
0
102
104
106
108
1010
Time (fs)
Power(W)
0 10 20 30 40 5010
0
102
104
106
108
1010
Time (fs)
Power(W)
Seed laser parameters
FWHM 0.5 fs
Power 10.0 MW
Pulse energy 5 nJ
FEL output parameters
Saturation FWHM 0.75 fs
Saturation power ~2.0 GW
Saturation energy 1.5 mJ
FWHM linewidth 6.0E-4
Undulator length 20 m
GINGER simulation of
seeded FEL at 0.3 nm.
Same ebeam parameters as SASE case.
0 10 20 30 40 500
0.5
1
1.5
2
Time (fs)
Power(GW)
0 10 20 30 40 500
0.5
1
1.5
2
Time (fs)
Power(GW)
24.5 25 25.5 26 26.5 270
0.5
1
1.5
2
Time (fs)
Power(GW)
24.5 25 25.5 26 26.5 270
0.5
1
1.5
2
Time (fs)
Power(GW)
-
8/3/2019 ASAC Introduction
27/47
Seeding for narrow linewidth
Output time profile Time profile (log plot) Spectrum
Seed laser parameters
FWHM 50 fs
Power 0.1 MW
Pulse energy 5 nJ
FEL output parameters
Saturation FWHM 30 fs
Saturation power ~2.0 GW
Saturation energy 0.1 mJ
FWHM linewidth 1.0E-5
Saturation length 28 m
GINGER simulation of
seeded FEL at 0.3 nm.
Same ebeam parameters as SASE case.
0.2995 0.3 0.3005 0.3010
100
200
300
400
500
Wavelength (nm)
Power(MW/bin)
0.2995 0.3 0.3005 0.3010
100
200
300
400
500
Wavelength (nm)
Power(MW/bin)
0 10 20 30 40 500
0.5
1
1.5
2
Time (fs)
Power(GW)
0 10 20 30 40 500
0.5
1
1.5
2
Time (fs)
Power(GW)
0 10 20 30 40 5010
0
102
104
106
108
1010
Time (fs)
Power(W)
0 10 20 30 40 5010
0
102
104
106
108
1010
Time (fs)
Power(W)
-
8/3/2019 ASAC Introduction
28/47
Comparison of SASE and Seeded Sources with APS Undulator A
-
8/3/2019 ASAC Introduction
29/47
-
8/3/2019 ASAC Introduction
30/47
Cost Basis
Fixed Costs 80 M$
(Gun, X-ray Beamlines, Buildings, Cryoplant, Controls)
Linac Systems (20 MeV/m, ~0.4M$/m) 20 M$/GeV
Undulator Systems (0.2 M$/m)
20M$/100mTotal Undulator Length = 4 x longest saturation length
Contingency 25%
-
8/3/2019 ASAC Introduction
31/47
Example
4 GeV Linac
50 m Saturation Length
Costs: 80 M$ Fixed
80 M$ Linac
40 M$ Undulators
50 M$ Contingency------------
250 M$ Total
-
8/3/2019 ASAC Introduction
32/47
1
10
100
1000
0 5 10 15 20
Electron Energy (GeV)
SaturationLength(m)
-
8/3/2019 ASAC Introduction
33/47
1
10
100
1000
0 5 10 15 20
Electron Energy (GeV)
SaturationLength(m)
100 nm
Electron Bunch ParametersQ = 0.5 nC E/E = 0.02% T = 250 fs
= 1.5 m
Hybrid Undulator ParametersVISA: = 18 mm, K=1.4, B=0.8 T23mm: = 23 mm, K=2.4, B=1.1 T
LCLS: = 30 mm, K=3.9, B=1.4 T
10 nm
1 nm
0.3 nm
0.1 nm
0.15 nm (LCLS)
u = 18 mmu = 23 mm
u = 30 mm
H b id U d l t P t
Better GunS d ti U d l t
-
8/3/2019 ASAC Introduction
34/47
1
10
100
1000
0 5 10 15 20
Electron Energy (GeV)
SaturationLength(m)
100 nm
Electron Bunch ParametersQ = 0.5 nC E/E = 0.02% T = 250 fs
= 1.5 m
Hybrid Undulator ParametersVISA: = 18 mm, K=1.4, B=0.8 T23mm: = 23 mm, K=2.4, B=1.1 TLCLS: = 30 mm, K=3.9, B=1.4 T
10 nm
1 nm
0.3 nm
0.1 nm
= 0.75 mSuperconducting Undulator = 14 mm K = 1.3
Superconducting UndulatorMiracle Gun = 0.1 m
-
8/3/2019 ASAC Introduction
35/47
Essential to Improve e-Gun Performance
In linacs, electron emittances scale inversely with energy
Electron beam emittance is born at the electron gun
Electron gun emittances today are ee = 0 .5 nm/E (GeV)
Photon emittances for full transverse coherence ep = lp/4
To couple a given electron beam most effectively to a
coherent photon field, we should have:
ee = ep
-
8/3/2019 ASAC Introduction
36/47
0.3 nm 0.1 nm
UV Hall X-ray Hall
Nanometer Hall
SC Linac
4 GeV2 GeV1 GeV
1 nm
0.3 nm
100 nm
30 nm
10 nm
10 nm
3 nm
1 nm
Main oscillator
Pump
laserPump
laser
Seed
laser
Seed
laser
Seed
laser
Pump
laser
Fiber link synchronization
Injector
laser
Undulators
Undulators
Undulators
Upgrade: 0.1 nm
at 8 GeV
SC Linac
MIT X-ray Laser Concept
-
8/3/2019 ASAC Introduction
37/47
The MIT X-ray Laser Project
A National User Facility: 10-30 beams
Wavelength range 100-0.1 nm
Integrated laser seeding for full coherence
Pulses: Dt=1-1000 fs; Dw=3-0.003eV
Pulse power of up to 1 mJ
Pulse rates of 1 kHz or greater
MIT/ Bates Laboratory
Science:single molecule imaging,femtochemistry, nanometer lithography
Technology:superconducting FEL,Ti:Sapp HHG seeding technology
Education:accelerator science curriculum, synergy with CMSE programs
Cost/Schedule:$300M; design: FY04-FY06; construct: FY07-FY10
-
8/3/2019 ASAC Introduction
38/47
MIT Commitment
MIT has embraced the x-ray laser conceptexclusively for the future of Bates Laboratory
Deans of Science and Engineering and the VP of
Research provided over $400K in seed support
President Vest asked a key CEO to chair a
corporation-level advisory committee to securesupport of business and political leaders in MA
-
8/3/2019 ASAC Introduction
39/47
Charge to
MIT X-ray Laser
Accelerator Science Advisory Committee
September 18-19, 2003
The proposed MIT x-ray laser facility is at an early stage ofconceptual design. The goals of the design are to produce fully
coherent x-ray pulses with the stable and reliable operations
required of a user facility. We seek guidance and constructive
criticism regarding the technical choices that are being made.
-
8/3/2019 ASAC Introduction
40/47
The ASAC committee should:
Review laser and accelerator sections of proposal to NSF and
technical presentations at committee meeting.Evaluate the appropriateness of chosen technologies and suggest
alternatives.
Identify the primary technical challenges for each system and for
the facility as a whole.
Respond to NSF reviewer comments.
Evaluate the potential for a facility based on the Bates linac to
demonstrate laser seeding and cascaded HGHG, and selectedscientific applications
-
8/3/2019 ASAC Introduction
41/47
MIT X-ray Laser Design Proposal
Contact: David E. Moncton, Director
Telephone: 617-253-83333
E-mail: [email protected]
website: http://mitbates.mit.edu/xfel/indexpass.htm
Bates Senior Staff Contributors
Manouchehr Farkhondeh William M. Fawley James Fujimoto
Jan van der Laan Hermann Haus Erich Ippen
Christoph Tschalaer Ian McNulty Denis B. McWhan
Fuhua Wang Jianwei Miao Michael Pellin
Abbi Zolfaghari Mark Schattenburg Gopal K. Shenoy
Townsend Zwart
Co-Principal Investigators Science Collaborators
William S. Graves Simon Mochrie Keith A. Nelson
Franz X. Kaertner Gregory Petsko Dagmar Ringe
Richard Milner Henry I. Smith Andrei Tokmakoff
3-year duration, $15M total request
-
8/3/2019 ASAC Introduction
42/47
Existing Technology
Electron Guns
Adequate performance has been demonstrated.
Room for continuing R&D and improvement.
Not a cost driver.
-
8/3/2019 ASAC Introduction
43/47
Existing Technology
Linac
Successful operation at Tesla Test Facility, JLAB.
Capital cost driver.
-
8/3/2019 ASAC Introduction
44/47
Existing Technology
Undulator
Well established. Successful experience at LEUTL, TTF.
Make use of investment in LCLS design.
Capital Cost driver.
-
8/3/2019 ASAC Introduction
45/47
3 e r st d l n
-
8/3/2019 ASAC Introduction
46/47
3-year study plan
-
8/3/2019 ASAC Introduction
47/47