LASER TECHNOLOGY FORACCELERATOR
Alexander S. Aryshev, Ph.D.
Assistant Professor
KEK: High Energy Accelerator Research Organization,
1-1 Oho, Tsukuba 305-0801, Ibaraki-ken, Japan.
TEL: +81-298-64-5715.
e-mail: alar@post.kek.jp

高エネルギー加速器セミナーOHO’20,
8 – 11 September 2020

LASER
Light Amplification by Stimulated Emission of Radiation

courtesy Dr. L. Corner, University of Liverpool
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Laser types
Lasers come in many different styles:• Temporal structure - continuous wave (cw) or pulsed (down to femtoseconds).
• Wavelength - X-ray free electron lasers through visible to near infrared fibre
and solid state systems, mid infrared quantum cascade lasers to 10.6mm CO2
lasers.
• Low power (barcode scanners, laser pointers).
• High peak power (100s TW, PW systems available commercially).
• Need to consider what it is required for your application.
• Overspec – makes it very expensive!

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Laser properties•They produce highly
directional beams.

•They have a "narrow"spectrum (bandwidth).

•They are spatially andtemporally coherent.

Diagram courtesy Prof. S. Hooker, Oxford
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Laser applications in accelerator physics• Many applications of laser technology.
• Broadly 2 categories:• Improving standard accelerators – diagnostics, timing, photocathodes.
• Driving new accelerators – laser driven plasma accelerators, dielectriclaser acceleration, direct laser acceleration in vacuum.
•
•
•
•
•

Laser-based particle sources
Laser-driven particle beam acceleration
Lasers for beam diagnostics
System integration
Laser and photon detector technology

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5Lasers for particle beam diagnostics• Electro-optic methods for bunch length measurement.

•
•
•
•

Coulomb field of the particle bunch alters the optical properties of the nonlinear crysta
Changes polarisation state of laser propagating through crystal.
Laser is chirped so spectral features directly relate to time.
Particle bunch length measured single shot and non-destructively.
See for example:• Pan et. al., MOPME077, IPAC 2013.
courtesy Dr. L. Corner, University of Liverpool
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6Lasers for particle beam diagnostics• Laser based beam size measurement.
Laser system – choice of parameters

Particle beam – energy,
temporal structure

Beam transport

Beam separation and extraction

Detection

Post – IP – diagnostics, energy, beam dumping• Measure electron beams (Compton scattering) - SLC, ATF2.
• Also ion beams (photo-neutralisation) - H- laserwire at Linac 4, CERN.
See for example:• Nevay et. al., Phys. Rev. ST Accel. Beams 17, 072802 (2014).
• Kruchinin et. al., MOPWI003, IPAC 2015.
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Lasers for particle beam diagnostics•

Measuring really small beam sizes• For < 1mm beams need something different – can’t focus laser spot to much less thanthis.
• Cross 2 laser beams at large angle to make very narrow interference fringe pattern.
• Scan interference fringes across beam and look for modulation in Compton signal.
• This monitor is *really* hard to align and make work well. Requires very stable laser
source.
See for example:• White et. al., Phys. Rev. Letts. 112, 034802 (2014).
• Yan et. al., 261, TIPP 2014.

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ATF2 laser-wire

•
•
•
•

ATF2 major international collaboration – scaled test of ILC optics.
Aim – electron beam size < 40nm.
Major test of new diagnostics – high resolution (< 5nm) bpms, fast feedback etc.
Laser-wire designed for highest resolution – measurement ~ 1mm.

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ATF2 laser system
SHG – 532nm, 100mJ

Linear amps up to 500mJ

Seed laser @ 357MHz locked to
sub-multiple of accelerator frequency

Seed pulse injected into Nd:YAG
flashlamp pumped regenerative
amplifier – 1.56Hz, 200ps, 10mJ

Image courtesy Dr. L. Nevay, RHUL

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Detection
Photons extracted through 1mm Al window
Detector placed next to window

Dipole magnet separates
electrons and photons

Cherenkov detector – g converted to e-/e+ pairs in lead, generate Cherenkov
radiation in aerogel, guided to PMT below beam line.
Photo courtesy Dr. L. Nevay, RHUL
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Results and analysis
Electron beam aspect ratio very large – cannot assume laser same size across particle
beam.

Try to model laser propagation and solve full overlap integral for particle and laser
beam
distributions – complex analysis because of electron beam size and laser properties –notjust simple adding of beam sizes in quadrature.
laser scane-

~ few mm~ few 100 mm

See Nevay et al., PR STAB 17, 072802 (2014)
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Preliminary scans and analysis

Horizontal scan –sex = 236.9 ± 2.98mm

Vertical scan – sey = 1.09 ± 0.22 mm
Demonstrated 1mm beam size
measurement – scan ~ 2 min.
Data: L. Nevay, A. Aryshev, L. Corner
Analysis: L. Nevay
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Timing and synchronisation in particle accelerators• Modern large accelerators and free electron laser complexes need timing
synchronisation for components such as beam, diagnostics, data acquisition at thefslevel or even < fs.
• Fibre based distribution of signals derived from mode-locked pulsed lasers are
now in use or planned at several facilities worldwide.
• As well as distributing a signal ‘clock’ need to be able to measure jitter and correctfor it.
• Measurements of jitter between mode locked lasers using optical techniques has
shown < 100 fs as jitter measurement.

See for example:• Peng et. al., Optics Letters 21, 19982 (2013)• https://desy.cfel.de/ultrafast_optics_and__x_rays_division/research/timing_distribution_and_synchronization/
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Lasers driving accelerators – plasma wakefield accelerators– Conventional accelerators are widely used in science and medicine.
• Acceleration gradient limited by electrical breakdown to < 100 MV/m.
• This sets the size (& cost) of the machine.

Diamond, UK

LHC

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Plasma accelerators – how they work
– Ponderomotive force of an intense laser
pulse expels electrons from the region of
the pulse to form a trailing plasma
wakefield.
– The wakefield moves at speed of laser
pulse (i.e. close to speed of light).
– Electric fields within wakefield canaccelerate charged particles.
– Huge accelerating gradients – 1000 x
conventional accelerators.
– 4 GeV in 9cm.
– 3.25 GeV in 14mm.
– Massive potential for reducing size andcost of particle accelerators.
Diagram courtesy Prof. S. Hooker, Oxford

See for example:• Esarey et. al., Rev. Mod. Phys 81 1229 (2009)• Kim et. al., Phys. Rev. Letts. 111 165002 (2013)
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Laser plasma accelerators - What’s the catch?
• Sounds great – why aren’t all accelerators plasma based?
• Mainly driver problems – lasers required are 100s TW or PW, inefficient so heatup, only fire once an hour/every 20 mins.
• Even fastest PW laser in the world only fires at 1Hz – too slow for realapplications.
• Also length of accelerator – only over ~ 10cm so far, need to show that many
stages can be put together to get to really high energy.
• Quality of electron bunches not as good as conventional accelerators yet.
• These are all active areas of research.
• Not forgetting laser driven proton and ion acceleration, and positron acceleration.
courtesy Dr. L. Corner, University of Liverpool
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Dielectric laser accelerators

Slide courtesy Dr. P. Hommelhoff, Friedrich-Alexander-Universitat, Erlangen
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Dielectric laser accelerators• New area of accelerator research.
• Have shown acceleration of relativistic and non-relativistic electrons using laserand dielectric structures.
• Also beam manipulation e.g. deflection for use as beam position monitor.

https://www.liv.ac.uk/quasar/research/novel_accelerators/

See for example:• Breuer et. al., Phys. Rev. ST Accel. Beams 17 021301 (2014)• Peralta et. al., Nature 503 91 (2014)
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Direct laser acceleration in vacuum

arXiv:1501.05101

•
•
•
•

Light has a strong electric field – can we use this to accelerate electrons?
How to get large on axis component? Focus radially polarised light beam.
Vacuum acceleration – no medium to breakdown, not unstable.
Carbajo et. al. Phys Rev. ST Accel. Beams 19, 021303 (2016) shown 3GeV/m –exciting result!
courtesy Dr. L. Corner, University of Liverpool
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Lasers as particle sources - Photocathodes• Can use laser pulses to produce electron bunches from photocathodes.
• Give bunches as short as the laser pulse without additional manipulation.
• Properties of the bunch can be controlled by the laser pulse shape in time andspace.
• Laser must be stable and locked to RF for further acceleration.
• Light needed at energies > photocathode workfunction, generally UV.
• Laser needs second or third harmonic frequency conversion due to PC Q.E.
• Large area of laser research – need:• High pulse energy• Reliable running• Excellent pointing stability

See for example:• Penco et. al., Phys. Rev. Letts. 112 044801 (2014)• Schreiber et. al., NIM A 445 (2000).

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Making a laser• All laser oscillators (as opposed to amplifiers) have 3 parts:• Gain medium – gas, solid state, liquid – what provides the lasing transition.
• Pump – source of energy to create population inversion – usually another lightsource e.g. flashlamp or another laser, can be electrical discharge or current.
• Cavity – need to recirculate photons to stimulate emission on lasing transition –often mirrors around gain medium, can be medium itself.
• Lasing threshold – when gain (no. photons emitted in round trip) exceeds loss
(number lost to absorption, through mirrors etc.).
• And that’s it!
courtesy Dr. L. Corner, University of Liverpool
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Typical laser pulse parameterrequirements for RF gun photocathode• Pulse energy, > 10uJ for Cs2Te• Pulse duration, ~ 100fs – 10ps
– Space-charge limited• Wavelength, ~ 250nm for Cs2Te– Hence, High Harmonic Generation is needed– Conversion efficiency depends on pulse duration and harmonic• Pulse repetition rate
– Hz (machine), MHz (multi-bunch), GHz-THz (micro-bunch)• Timing stability, < 1ps (~1 deg. RF phase (2.8GHz))– Stabilized and synchronized oscillator– Stabilized Laser Transport Line

• Pointing stability, smaller than rms spot size, typ < 100um.
– Stabilized Laser Transport Line
– Additional spatial filters• Spatial and temporal pulse shaping– Pulse stacking– Micro-lens arrays– -shapers
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Typical technology (effectively dopants)Ion
3+

neodymium(Nd )3+ytterbium(Yb )3+erbium (Er )3+thulium (Tm )3+holmium (Ho )3+cerium (Ce )Ion
3+titanium (Ti )2+chromium (II) (Cr )3+chromium (III) (Cr )4+chromium (IV) (Cr )Common host crystals

Important emission wavelengths

Y3Al5O12 (YAG), YAlO3 (YALO), YVO4 (yttrium vanadate), YLiF4 (YLF), tungstates (KGd(WO4)2, KY(WO4)2)

1064, 1047, 1053, 1342, 946 nm

YAG, tungstates (e.g. KGW, KYW, KLuW), YVO4, borates (BOYS, GdCOB), apatites (SYS), sesquioxides (Y2O3,
Sc2O3)

1030, 1020–1070 nm

YAG, YLF

2.9, 1.6 μm

YAG

1.9–2.1 μm

YAG

2.1, 2.94 μm

YLF, LiCAF, LiLuF, LiSAF, and similar fluorides

0.28–0.33 μm

Common host crystals

Important emission wavelengths

sapphire

650–1100 nm

zinc chalcogenides such as ZnS, ZnSe, and ZnSxSe1−x

2–3.4 μm

Al2O3 (ruby), LiSrAlF6 (LiSAF), LiCaAlF6 (LiCAF), LiSrGaF6 (LiSGAF)

0.8–0.9 μm

YAG, MgSiO4 (forsterite)

1.35–1.65 μm (YAG), 1.1–1.37 μm(forsterite)

Nd:YAG

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RF Gun laser system technologies
Solid-state-based technology

Fiber-based technology

Hz rep.rate
fs pulseHigh Energy
Complexity

Ti:Sa

Nd:YAG

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Yb-dopped fiber for example

Hz rep.rate
ps pulseHigh Energy
Simplisity

courtesy Y. Honda

MHz rep.rate~100 fs pulse
Low Energy
Simplisity

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A. Chong, W.H. Renninger, F. W. Wise, Opt.
Lett. 33 (2008) 2638:

Numerical simulations of Yb-doped fiber
lasers indicate that ~30 fs pulses are
possible for a realistic design with offthe-shelf components. Experiments areconstrained by the available pump
power, but ~75 fs pulses are obtained.
(just for oscillator !!!)

Er-doped fiber laser is also promising candidate

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What is so Special About ps-fs Lasers?
•
•

•

•
•

Short optical pulse.
Most of energy dissipation andtransfer processes occur on thetime scale larger than 100 fs.
Femtosecond laser pulses enable
one to generate electron buncheswith similar durations (strongly
related to generation of THz
radiation).
Specific laser system design
approaches.
Specific gain materials due tooptical BW and efficiency with fs
pulses.
Specific pulse diagnostics.

High peak power of the light• Peak Power = P. energy / P. duration– 1 mJ pulse with 10 ns duration - 0.1 MW.
– 1 mJ pulse with 100 fs duration - 10 GW.

• Non-linear response of the opticalcomponents(e.g., multi-photon
absorption, optical harmonics
generation, materials ablation, etc.)
Large bandwidth• Broadband optical components(mirrors, etc)
• Achromatic lens, waveplates, etc.
• Higher demands for laser safety.

W. Kaiser, ed., “Ultrashort Laser Pulses: Generation and Applications”, Springer-Verlag, Berlin, 1993
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Chirped
pulse amplification
Amplificationof fs Pulses concept
•
•
•
•
•
•
•
•

Generate a stable (and locked to Acc. RF) sequence of fs pulses (Oscillator)
Stretch femtosecond pulse to picoseconds level ( > 100 times)
Pulse pickers, mode cleaners, etc
Pre-amplify (typically RGA for Solid-state lasers)
Amplify
Recompress amplified pulse
Generate Harmonics
Deliver laser pulses to the photocathode• With additional spatial corrections and diagnostics

Oscillator

Stretcher

AmplifierCompressor

Same approach works for fiber lasers with the only difference in available components.
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•Time-Frequency RelationshipA pulse can be defined as a transient in a constant background. The shape of thispulse is the shape of this transient. Intuitively, the pulse shape can be
represented by a Gaussian function. It is known that the Fourier transform of a
Gaussian function is also a Gaussian function. The general time and frequency
Fourier transforms of a pulse can be written as:•

The relationship between the duration and spectral
bandwidth of the laser pulse can be written as:•

where  is the frequency bandwidth measured atfull-width at half-maximum (FWHM) with  = 2
and t is the FWHM in time of the pulse and K is anumber which depends only on the pulse shape.
Consider it as a homework ->•Thus in order to generate a laser pulse within femtosecond time domain one
needs to use a broad spectral bandwidth. If the above equality is reached, one
speaks about a Fourier-transform-limited pulse or simply a transform-limited
pulse. One can also calculate the minimum time duration t of a pulse giving aspectrum with  (nm) at FWHM, central wavelength 0 (nm) and the speed oflight (m/s) c as:
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Time-Frequency Relationship

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Basic principles of ultrafast lasers
Components of ultrafast laser system
Mode-locking

Pump

Dispersion

HR

Gain

OC
Mechanism

Compensation

Cavity modes

n = 2 L/n
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2020
n – positive
integer f = c/2 L
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frequency separation between adjacent modes

Mode-locking• Ignition– Dispersive pulse compression –external starting mechanism.
– Instantaneous increase in net gain
(Kerr lens) upon application of
perturbation (mirror wobbling, truly
self-starting).

• Passive mode-locking– Semiconductor Saturable Absorber
Mirrors (SESAM), ps pulses– Kerr lens
– Nonlinear polarization rotation(NLPR)– Q-switched Mode Locking, effectively
instability.

• Active mode-locking

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– Periodic modulation of the resonatorlosses or of the round-trip phasechange, achieved e.g. with an acoustooptic or electro-optic modulator, aMach–Zehnder integrated-optic
modulator, or a semiconductor
electro-absorption modulator.
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Ti:SaOscillator

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•

Fiber Oscillator
Andy Chong, “All-normal-dispersion femtosecond
Fiber laser”, Vol. 14, No. 21 / OPTICS EXPRESS
10095, 2006

Cp1 

•

MT
PZT
EM

Reflective
gratings

G1

G2

Is2
DM

LD1

PBS
Yb-fiber 1

Is1
WDM1

•

G2-MT



Cp2

•
•

Nonlinear polarization rotation(NLPR)：– A power-dependent polarization change is converted into a
power-dependent transmission through a polarizer. NLPR
converts the differential phase shift to amplitude modulation.
••••

stable soliton
stretched-pulse
self-similar
all-normal-dispersion pulse

Solitons are caused by a cancellation of nonlinearity anddispersion.
For stable soliton fiber lasers the energy of a single pulse
is limited by the nonlinear phase shift induced by thehigh peak power. The pulse will break into multiple
pulses when the energy rises to 0.1 nJ.
Analog to dispersion-managed soliton, an alteration of
positive and negative dispersion part inside a laser cavity.
Produce highly desirable Gaussian pulse shapes andbroad pulse spectra.
SMF: Single-mode fiber
NPE: Nonlinear polarization evolution

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Stability
95 MHz, 20ns/div

95 MHz, 5us/div

95 MHz, 20ms/div

112 MHz, 10ns/div

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Rep.rate and BW
Output power was 110mW, rms stability 0.25%
129 MHz, 10ns/div

Contrast: 37mV/377mV = 0.098

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Spectral width
Further tuning should be applied to flatten
peaks of emitted spectrum

FWHM optical BW > 25nm
Emission

Absorption
2500

1000

1500

Intensity, arb. units

Intensity, arb. units

2000

1000

500

100

10

1
0

-500
960

980

1000

1020

1040

1060

0.1
960

980

Wavelength, nm

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1000

1020

1040

1060

Wavelength, nm

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Oscillator performance with small
dielectric end-mirror~ 135mW, 0.2% rms stability

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Oscillator performance with small
dielectric end-mirror

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Dispersion and Group velocity
•
•
•
•
•

Dispersion in Optics: The dependence of the refractive index on wavelength has
two effects on a pulse, one in space and the other in time.
“Chirp” d2n/d2 and “Angular dispersion” dn/dBoth of these effects play major roles in ultrafast optics.
Dispersion disperses a pulse in space (angle):
Dispersion also disperses a pulse in time:Group Velocity Dispersion (GVD)• v = c / n – speed of light ina medium• n –depends on wavelength,dn/d < 0 – normal dispersion••

Because of GVD, red components (longer
wavelengths) of the pulse propagate faster thanblue components (shorter wavelengths) leading
to pulse stretching (aka “chirp”).
GVD can be compensated by material with
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abnormal dispersion.

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Group-Velocity Dispersion

The effect of group velocity dispersion• GVD means that the group velocity will be different for different
wavelengths in the pulse.
• Because ultrashort pulses have such large bandwidths, GVD is a bigger issue
than for cw light.
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Stretcher and Compressor“Aberration-free stretcher design for ultra-short pulse amplification” G. Cheriaux, F. Salin and
al. OPTICS LETTERS March 15 1996

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Pre-amplifier. RGA

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Amplifier

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Ti:Sa Laser system: general layout
Compressor

Stretcher

Autocorrelator

THG

LTL

Buncher

RGA

Oscillator
Cathode10 September 2020

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Harmonics

Frequency tripling is a process of a nonlinear frequency conversion.

frequency
doubler

BBO, Type1
 = 29.2deg
~ 90deg
L= 0.2mm

sum frequency
mixer

Calcite= 45deg
L= 1.7mm

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Achromatic
Half-wave plate~ 90deg
L= 2mmBBO, Type1
 = 44.3deg
~ 90deg
L= 0.05mm

THG 𝞴/2 GVD

SHG•
C. Radzewicz, Optics communications 117 (1995) 295-302.
•
Lixin YAN, Preliminary Experiments on Ultrashort Bunch
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Train Production by UV Pulse Stacking, Tsinghua University

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Multi-micro-bunch, concept
RF, 2856 MHz
4 micro-bunches
1 multi-bunch (1 RF bucket)
3.13 HzRF, 2856 MHz• Number of filled RF buckets depends only
on FH laser energy budget• Non-sequential RF bucket filling is possible
4 micro-bunches
4 multi-bunch (4 RF buckets)

3.13 HzRF bucket period ~350ps
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• DAQ sees this micro-train as a single event(no trigger modification is required)• Micro-bunch spacing changing
simultaneously in all buckets
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“Buncher”, second (current) prototype
General sheme of 16-buncher

Photo of pre-assembled buncher

 All bits were delivered in September 2014.
 Assembled and tested (laser side only) in Nov.-Dec. 2014
 Tested (e-beam generation) in Jan. – Feb. 2015
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FSTB: fs Single Shot cross-correlator
The method based on theregistration of crossdistribution of Second
Harmonic (SH) energy
produced in nonlinear
crystal under noncollinear interaction of
two beams withdetermined aperture.

A

SHG Crystal

B

C

B
C
A
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Ti:Sa laser system (FSTB)

Operational parameters

Original

4
years
later

Repetition rate, max

10Hz

3.13HzCentral wavelength

795nm

795nm

Pulse energy before compression

22mJ

5mJ

Pulse energy after compression

14mJ

3mJ

Pulse duration w/w-o correction

30/37.7fs

50fs

Energy stability 22mJ@800nm

1.6%

3%

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•
•
•
•
•

Entire infrastructure was built
Control soft 80% re-written
Additional pulse diagnostics introduced
THG simulated, ordered, built
2 buncher systems were implemented

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Multi-micro-bunch, implementation
Present condition: 4x4 pulses, ~50 fs each, converted to 266nm, 10uJ

•
•
•
•
•

Total splitting efficiency ~20%
New design with total 10-20% loses is possible.
Beam expander was removed.
Multi-pass Amp, Compressor, THG, LTL re-tuned.
Micro-bunch––•

Separation: +/- 5 ps
Stability: < 20 fs (lower than meas. resolution)

Multi-bunch–

Separation: 350ps +/- 30 ps
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Motorized delay control
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Manual delay control
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Ir7
DM1

Ir6



M11



Pre-amplifier, PCF and modified laser
system diagram
L13
f=...

DM26

DM16
PCF-ROD1

LD4



GR3

BBO1

M10
L11
f=...

Ir5

ASE4
GR2

Is4

M8

MC1

L10
f=...

DM24

M7

DM14
DMP3

PCF-ROD1

LD3

M12

M9

PBS4

ASE3

BBO2

LTL+FF

DM15

Cp6 L12
f=...



L14
f=...

DM25



MS
L15
f=...

DMP4

DM23

M6

DM13
L8
f=...

Cp5 L9
f=...

Ir4
L5
f=20 Cp3

LD1
Yb-fiber 1

M0


PBS1
Ir1

M2

Cp2

Is1

BS2 Cp0

M1

To Optical
spectrometer

Is3



M3

M3
BS1

Is3
M4

Cp

M4

WDM1

10 September 2020

高エネルギー加速器セミナーOHO’20

L6
f=20



L7
f=20

DM21

DM11

Is4

PCF

Cp4

LD2

SOA
Cp

PBS3


L3 PD1
f=150

DM22

MT
PZT
EM
BPF1
Is2



Cp1



DMP2 DM12

ASE2
M5
ASE1

53

Whole system (Osc. + Pre.amp)

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54

Pre. Amp tests

Current(A)
6.3
9
12.2
15
17
19.1
20.2

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高エネルギー加速器セミナーOHO’20

Out Put pump power (mW)
24
135
300
521
752
1050
1230

55

Pre. Amp. tests

56

LUCX-FSTB-THz, 3D model
Modulator #0

Nd:YAG

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Ti:Sa

57

LUCX laser transport line (LTL)
Box #1

Nd:YAG table
Concrete wall

FSTB table

Box#2

Difficulties:
1. Selecting either of two laser beams: Nd:YAG of Ti:Sa
2. Separate focusing systems.
3. Same FF and “virtual cathode”
4. Relatively long optical path
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高エネルギー加速器セミナーOHO’20

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60

高エネルギー加速器セミナーOHO’20

Final Focus diagnostics
CCD

iris

iris

PD
iris

iris

61

Conclusion• Lasers are a vital part of modern particle
accelerators.
• It is used as diagnostics, timing systems, sources ofparticles, drivers of new accelerators.
• Research and development of new laser sources will
drive improvements in:– Particle accelerators – smaller, cheaper, more efficient.
– Particle temporal distribution (important for light sources– THz FELs, Compton, etc)
– Particle beam diagnostics
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高エネルギー加速器セミナーOHO’20

62

Materials• Jean-Claude Diels, Wolfgang Rudolph: “Ultrashort laser pulse
phenomena”, Second edition, 2006
• Tone Rotar, “Ultrashort laser pulses”, Ms Thesis.
• Carlo Antoncini, “Ultrashort Laser Pulses”, Lecture notes.
• Yuelin Li, ANL, 2008 USPAS, summer session lecture notes.
• Valerii Ter-Mikirtychev, “Fundamentals of Fiber Lasers and Fiber
Amplifiers”, Springer, 2014
• Yan YOU, “Yb-doped Mode-locked fiber laser based on NLPR”,
2012• Alexander Mikhailovsky, “Basics of femtosecond laser
spectroscopy”• Jeremy R. Gulley, “Simulation of Ultrashort Laser Pulse
Propagation and Plasma Generation in Nonlinear Media”.
• S. LI et al. PHYS. REV. ACCEL. BEAMS 20, 080704 (2017)• H. Tomizawa, “Adaptiveaptive3D-Laser pulse shaping System to
Minimize Emittance for Photocathode RF gun”, WEBAU01, FEL
2007• L. Corner, Lasers in Particle Accelerators, CERN Accelerator
Course, Budapest 11th Oct 2016
63

Thank you very much!

64
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高エネルギー加速器セミナーOHO’20