instrumentation in free electron laser...free electron laser [email protected] natal – september 10...
TRANSCRIPT
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Instrumentation in
Free Electron Laser
Natal – September 10 - 2016
INTERNATIONAL SCHOOL ON LASER-BEAM INTERACTIONS
Geraldo Cernicchiaro
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Outline
• Free Electron Laser – Basic concepts
– Low gain regime
• Transducers devices – Ondulator
– Eléctron Beam Transport
• System Control
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Laser
• Coherent
• Monochromatic
• Collimated
Solid State Laser
Gas Laser
Semiconductor Laser
Fiber Laser
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Most common Lasers
Mirrors – Resonant Cavity
optical amplifier
Energy
Excitation
Laser bean
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Argon fluoride (Excimer-UV)
Krypton chloride (Excimer-UV)
Krypton fluoride (Excimer-UV)
Xenon chloride (Excimer-UV)
Xenon fluoride (Excimer-UV)
Helium cadmium (UV)
Nitrogen (UV)
Helium cadmium (violet)
Krypton (blue)
Argon (blue)
Copper vapor (green)
Argon (green)
Krypton (green)
Frequency doubled
Nd YAG (green)
Helium neon (green)
Krypton (yellow)
Copper vapor (yellow)
0.193
0.222
0.248
0.308
0.351
0.325
0.337
0.441
0.476
0.488
0.510
0.514
0.528
0.532
0.543
0.568
0.570
Helium neon (yellow)
Helium neon (orange)
Gold vapor (red)
Helium neon (red)
Krypton (red)
Rohodamine 6G dye (tunable)
Ruby (CrAlO3) (red)
Gallium arsenide (diode-NIR)
Nd:YAG (NIR)
Helium neon (NIR)
Erbium (NIR)
Helium neon (NIR)
Hydrogen fluoride (NIR)
Carbon dioxide (FIR)
Carbon dioxide (FIR)
0.594
0.610
0.627
0.633
0.647
0.570-0.650
0.694
0.840
1.064
1.15
1.504
3.39
2.70
9.6
10.6
Key: UV = ultraviolet (0.200-0.400 µm)
VIS = visible (0.400-0.700 µm)
NIR = near infrared (0.700-1.400 µm)
Material Science
Wavelength (mm) Laser Type
Laser Type Wavelength (mm)
The light from a laser typically comes from
atomic transitions with specific wavelength.
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FEL
Accelerator
Eletron beam
l
undulator
lu
mirror
mirror
• Long range tunability
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AltoGanho
1z
R. Bonifacio et al; Phys. Rev. Lett. 73, 70 (1994)
SASE Self Amplified Super Radiant Emission
SASE
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FELBE
REVIEW OF SCIENTIFIC INSTRUMENTS 80, 073102 (2009)
FELBE at the FZD in Dresden
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Permanent magnets
Steel pole
- Two arrays of permanent magnets blocks
- Sinusoidal Magnetic Field
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lu = 8 mm
Gap
Hybrid Undulator
lu = 8 mm
NdFeB
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Distribution of Bz Amplitude
11
Bz (
T)
x
Bz
Bz (
T)
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Magnetic Characterization
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Undulator
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Undulator
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Synchroton Radiation
= 1
1 – v2 / c2
If v c l = l’ (1 – v/c cos )
l lu
2 2
Undulator or Wiggler
(N periods)
l
“ When a particle with velocity v is deflected, it emits radiation.”
“ Relativistic particles emits in a charcteristic cone 1/ “
lu
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FEL Model
Relativistic
Electron beam
mirror mirror
Resonant cavity
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FEL Model
Relativistic
Electron beam
mirror mirror
Resonant cavity
Electromagnetic
Radiation
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FEL Model
Relativistic
Electron beam
mirror mirror
Resonant cavity
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Parametric coupling
Random electron phase
Electrons bunched at
Radiation wavelength
Incoherent emission Coherent emission
Radiation bunch
electrons Electrons bunched
emission coherent
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Tunability
0
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
0,8 0,9 1 1,1 1,2 1,3 1,4 1,5 1,6 1,7 1,8
Energia ( MeV)
lam
bda
(µm
)
λu = 16 mm
λu = 8 mm
λu = 4 mm
lu = 16 mm
lu = 8 mm
lu = 4 mm
Energie (MeV)
l (m
m)
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FELIX
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Electron Beam Transport
Quadrupole
Mirror reflectivity 100%
Centering monitor
Mirror reflectivity less
than100%
Accelerator
Undulator
Dipole
Electron Beam
Laser
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Dipoles
Deflexion
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Quadrupoles
Força Força
Convergence
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Energy Recovery
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Electron Beam Transport
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Centralization Device
Aperture Servomechanism
Fluorescent
Screen
CCD
Electron
Beam
Mirror Spot
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FEL Components
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Control System
Control Panel
TCP/IP
DAC
ADC Current Drivers
Power Control DAC – ADC
Interfaces
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Control Panel
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FREE ELECTRON LASERS
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FREE ELECTRON LASERS
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Thanks