HiLASE: New lasers for industry and research

HiLASE: New lasers for industry and research

HiLASE: New lasers for industry and research
Tomáš Mocek, Ph.D.
Chief Scientist & Project Leader
HiLASE Centre
CZ.1.05/2.1.00/01.0027
High average power, pulsed LASErs
•
Project led by the Institute of Physics ASCR
•
Financed by the Research and Development for
Innovation Operational Program (ERDF)
•
R&D Centre
•
DPSSLs with breakthrough parameters
•
Applications of DPSSL in high-tech industry
•
Synergy with ELI Beamlines
New HiLASE building
Laser technologies
Aiming very high
Laser pumping: flash lamps
Flash pumps
• use only small part of spectrum
• generate a lot of heat
• lifetime
• cheep
• high excitation energy
Spectrum
Heat
Useful radiation
Nd:YAG or Yb:YAG
Diode-pumped solid-state lasers
Yb:YAG absorption spectrum:
- Wavelength of Max.: 942 nm
- FWHM : ~ 18 nm
InGaAs emission spectrum:
- Wavelength of Max.: 939 ±
3 nm
- FWHM: ~ 4.5 nm
- Temperature shift: ~ 0.3 nm/0C
Upscaling novel DPSSL geometries
Thin-disk
diamond
substrate
Multi-slab
HR
coating
AR
coating
Cooling water
A
solder
Yb:YAG
thin disk
Al frame
Cr:YAG
Yb:YAG
∆T<4 K
∆T<60 K
Fin detail
Lasers for real-world applications
•
Laser
induced
damage
threshold
measurement of optical materials (LIDT)
•
Laser shock peening (LSP)
•
Compact XUV sources for lithography
•
Precise cutting, drilling and welding of
special materials for automotive and
aerospace industry
•
Technology of laser micromachining
•
Laser surface cleaning and processing
15%
Mission
UNIVERSITIES
education
15%
training
experimental
facilities
innovation
research
LABORATORIES
scientific
results
further
education
scientific
results
COMPANIES
Inspiration #1
T.H. Maiman:
the father of Laser
In line with current trends in Europe
HiLASE aims to be a GLOBAL player
Time schedule: 12 months ahead
01-08/2015
09/2015
03-06/2014
01-03/2013
09/2012
10/2011
09/2011
Decision on
grant
Start of
construction of
new building
Start of procurement
and in-house R&D of
key laser systems,
incl. construction
Signing
contracts for
key laser
systems
End of
construction,
relocation from
Prague to Dolní
Břežany
Installation
and
optimization
of key laser
systems
Commissioning
of HiLASE R&D
Centre
Cornerstone laying ceremony
October 9, 2012
Progress of construction: 03/2011
12/2013
07-08/2012: evaluation of STDR
•
International Expert Panel appreciated the Scientific
and Technical Design Report of the HiLASE project (STDR)
•
Critical evaluation of the STDR was provided by
independent experts with long-term experience from
Japan, India and USA
15%
•
The 167-page STDR consists of thorough
laser systems design solution proposals
for all HiLASE research programs
02/2014: Mid-term Review
CrewProject
complete:
launch:
71 heads
09/2011
(61 FTE)
Training at world top-class institutions
Research Programme 1
Development of multi-J, kW class
thin-disk laser system (L1)
Prof. Akira Endo
Thin-disk laser principle
diamond
substrate
HR
coating
AR
coating
Cooling water
Laser beam
solder
Yb:YAG
thin disk
Concept of kW-class thin-disk DPSSL
Beamline-A
750 m J, <3 ps, 1.75 kHz
Beamline-B
Beamline-C
Oscillator
Oscillator
1,3 kW
Sub-contract
Pulse stretcher
Pre
100 mJ, 1-2 ps, 1 kHz
100 W
Pulse compressor
Booster
Regenerative
Amplifier
Main
Pulse stretcher
Main
Regenerative
Amplifier
Cryogenic
Slab amplifier
Ring amplifier
Pulse compressor
Pulse compressor
Pulse compressor
1 J, 1-2 ps, 120 Hz
500 mJ, 1-2 ps, 1 kHz
5 mJ, 1-2ps, 100 kHz
120 W
500 W
500 W
Applications of our thin-disk lasers
X-ray source via
laser Compton
Soft X-ray source via
laser induced plasma or HHG
EUV micro-
machining
MID-IR pulse source for LIDT
Water window
applications
EUV/BEUV
metrology
Pre-pulse laser
for EUV/BEUV
lithography
MID-IR pulse source for
Bio-medical applications
A
B
C
Efficient EUV/BEUV source
Continuous dense gas jet target
Beamline B
ps laser
500 W
Xe, Kr, N2
Differential pumping
EUV / BEUV
New: 0.5 J, 1-2 ps, 1 kHz
Old: 0.5 J, 8 ns, 5 Hz
high brilliance
low debris
Pre-pulse Laser for HVM EUV Lithography
•
•
•
•
•
Solid-state laser
3 mJ
100 kHz
<10 ps
stable !
Beamline C
Pre pulse laser
CO2 lasers
High Energy Regenerative Amplifier with
pulsed zero-phonon-line pumping
COMPRESSOR
STRETCHER
HR
G2
OUTPUT
47 mJ @ 1 kHz
PC
lens
G3
λ\4 TFP
HR
PBS
λ\2
lens
G1
HR
HR
lens
HR
HR
FR
HR
HR
PBS
HR
HR
HR
HR
HR
HR
Thin-Disk
Laser head
HR
lens
969-nm
800-W
Fiber-coupled
laser diode
REGENERATIVE AMPLIFIER
Yb-doped fiber osc.
1030nm,
20nm FWHM,
2W@50 MHz
lens
OI
FRONT-END
HR
940-nm Pulsed Pumping in 1-kHz
Regenerative Amplifier
30 mJ, eff. 12.2 %
Pump
1-ms
0.3-0.9 ms
~285-W
Pulse
Length
900 µs
t
30 mJ, eff. 15.7 %
Pump
Pulse
Length
700 µs
24 mJ, eff. 19 %
Pump
Pulse
Length
500 µs
Improvement of O-O Efficiency via
Zero-Phonon Line Pumping
2.8 nm
(FWHM@969 nm)
Advantages of zero-phonon line pumping
• Lower quantum defect
8.7 % @ 940 nm
5.9 % @ 969 nm
• Less heat generated in the gain medium
Smaller deformation of thin disk
Higher pump density
969 nm
18 nm (FWHM@940 nm)
(ex.)VBG (Volume Bragg Grating) installed
narrowband laser diode
969 nm vs. 940 nm pulsed pumping
940 nm
969 nm
969 nm
M2 measurement of Beamline B
1/e2=40 µm
M2
Horizontal
Vertical
1.25
1.23
Beam pointing stability
RMS pointing stability:
Horizontal- 3.8 µrad
Vertical- 3.3 µrad
3,5
Vertical Displacement [µm]
2,5
1,5
0,5
-0,5
-1,5
-2,5
-3,5
-3,5
-2,5
-1,5
-0,5
0,5
1,5
Horizontal Displacement [µm]
2,5
3,5
Concept of cryo booster amplifier
Beamline C: upgraded to 85W (02/2014)
CVBG-based Pulse Stretcher & Compressor
λ/2
CVBG
(Chirped Volume Bragg Grating)
PBS
Mode-locked
Fiber laser
λ/4
•
•
•
•
•
•
•
λ/4
CVBGs designed for 2.2+-0.5nm bandwidth (FWHM)
Aperture 8x8mm
180 ps/nm dispersion
88% diffraction efficiency
Oscillator bandwidt approx. 20nm, i.e. 78.5% pulse energy losses in stretcher
Home-made oscillator is being developed
Compressor (grating) efficiency 87 - 88% (measured)
Beamline C: compressed pulse <2 ps
oscillator
CVBGs + regen + precompressor
M2 measurement of Beamline C
0.5
0.45
beam width [mm]
0.4
0.35
0.3
0.25
0.2
0.15
0.1
0.05
0
50
55
60
65
70
z position [mm]
75
80
85
X-direction
Y-direction
Waistdiameter 0.12 mm Waistdiameter 0.15 mm
Rayleigh Range 8.74 mm Rayleigh Range 15.77 mm
Divergence
13.67 mrad Divergence
9.80 mrad
M˛
1.25
M˛
1.15
90
Evaluation of Various Thin Disks
(in CW Multimode Laser Cavity)
8% OC
Thermal
camera
2.8 mm pump spot
Thin disk
R=5m
Soldered
thin disk
Cavity is stable over the wide range of thermal lensing focal length
Thin disk thermal lensing focal length [mm]
Thin disk on
diamond
substrate
Home-made thin-disk head
for 5-kW pumping
Home-made Fiber-Based Preamplifier
• 2-stage mode-locked fiber laser amplifier
• SOA pulse picker + YDFA amplifier
• 1-W output, 230 fs
In-house R&D:
12/2013
08/2012
07/2014
08/2014
Status of in-house development
47-mJ, 1-kHz
85-W, 100-kHz
50-W, 100-kHz
30-mJ, 1-kHz
50-W, 10-kHz
Jan. 2014
25-W, 100-kHz
Research Programme 2
Development of 100 J / 10 Hz
cryogenically cooled
multi-slab DPSSL system
scalable to kJ level (L2)
Dr. Antonio Lucianetti
Inspiration: Mercury
Project
Location
Mercury
USA
Application
IFE/Ti:sa
Gain medium
Yb:S-FaP
Temperature
cryo
Pulse energy [J]
60 (100)
Pulse duration [ns]
14
Rep.rate [Hz]
10
Center wavelength [nm]
1050
Pump wavelength [nm]
899
o-o efficiency [%]
6 (12)
Advantages of cryo cooling YAG
Cooling options for [100 J- kJ] class lasers
Multi-slab amplifier
Active mirror amplifier
Strategic partnership with STFC/RAL
D1
D2
D3
D4
D5
D6
D7
D8
D9
D10
D11
D12
D13
Beamline L2 under construction
Parameter
Specification
Pulse energy
> 100 J
Av. output power
> 1 kW
Pulse length
2-10 ns
Pulse shape
Programmable
(150 ps steps)
Repetition rate
1 – 10 Hz
Output beam size
75mm*75mm
(SG order > 8)
RMS modulation
< 1%
Wavefront quality
lambda/10
E-o efficiency
> 12 %
47
Complex numerical modeling
Wavefront
correction
Depolarization
ASE code
Heat transfer
OPD
MIRO modeling
Input
Calculation
Output
Responsible
stored energy, heat load
Magda S.
1)
Pump beam, geometry ASE modeling
2)
Heat load
Thermo-optical modeling
OPD, depolarization
Ondrej S.
3)
OPD
MIRO modeling
Output beam profile
Martin D.
4)
OPD
Wavefront correction
AO performance, wavefront
Jan P.
48
Modeling of multi-slab laser
•
•
In order to distribute the thermal loading amongst the slabs
equally, the doping of the slabs varies based on their position in
the multi-slab chamber
Doping varies between 0.3 at.% and 1.3 at.%
Thermo-optical modeling
He flow direction (160 K, 10 bar)
x
120
Yb:YAG
100
y
75
Cr:YAG
A.L. Bullington, S. B. Sutton, A. J. Bayramian, J. A. Caird, R. J. Deri, A. C. Erlandson,
M. A. Henesian ,”Thermal birefringence and depolarization compensation
in glass-based high-average-power laser systems’’, Proc. SPIE, vol. 7916 (2011).
O. Slezak, A. Lucianetti, M. Divoky, M. Sawicka,
and T. Mocek, "Optimization of Wavefront Distortions
and Thermal-Stress Induced Birefringence in a
Cryogenically-Cooled Multislab Laser Amplifier,"
IEEE Journal of Quantum Electronics, vol. 49,
pp. 960-966, 2013.
Average depolarization
after 24 passes: 9.6 %
Fluid Dynamics modeling
Pump Beam
•
•
Yb
doped
area
Cr
dope
d
area
He gas cooling
- Initial temperature: 160 K
- Inlet velocity: 10 m/s
- Max. velocity: 34 m/s
- Pressure: 5 bar
Non-symmetrical
temperature profile
Heat exchange in
turbulent boundary
layers
AO experimental test bench
•
Aberration
generator
•
The layout follows
the design of 10 J
system
•
•
20x20mm2
beam trace
Aberration
magnitude
•
Glass slab
•
2 heating beams
to simulate
heating of central
part and cladding
52/25
Experimental verification
•
Calculated aberrations
can be generated with
big precision
•
2 heating beams
simulate heating of
central part and
cladding of the slab
•
Various slab
geometries can be
simulated
•
Generated aberrations
can then be subject to
correction
53/25
Spectroscopy at cryo temperatures
Monochromator
Photomultiplier
We are also investigating other Yb-doped
materials:
Yb-doped silicate glasses,
Yb:YAP, Yb:LuAG, Yb:CaF2,…
Spectroscopic measurements
Absorption cross-section
Emission cross-section
55
10J/10Hz operation demonstrated at STFC
Using new high-resolution spectroscopic data of HiLASE
40 ns cryo laser cavity for LIDT tests
57
Cryo spectroscopy of Yb:YGAG ceramics
10at.%Yb:Y3Ga2Al3O12 with 2 mm in thickness and 18 mm in diameter ceramic
σa[10-20cm2]
1.5
1.0
0.5
0.0
850
340K
320K
300K
280K
260K
240K
220K
200K
180K
160K
140K
120K
100K
80K
60K
40K
20K
3,5
Yb :Y3Ga2Al3O12
1000
FL method
2,5
2,0
1,5
1,0
0,5
900
950
wavelength[nm]
Yb :Y3Ga2Al3O12
3,0
σe[10-20cm2]
2.0
pump
0,0
900
950
1000 1050 1100
wavelength[nm]
for sub-ps
pulses
340K
320K
300K
280K
260K
240K
220K
200K
180K
160K
140K
120K
100K
80K
60K
40K
20K
1150
Diode stacks characterization
Parameters
QCW
Central wavelength
Central wavelength
tolerance
Spectral width (FWHM)
Repetition rate (f)
Pulse duration (t)
Output power per stack
939 nm
± 2nm
< 5-6 nm
10 Hz
0.8-1.2 ms
> 2500 W
1) Diode stack
2) Wedge prism
3) Power meter
4) Integration sphere
5) CCD camera with nd filter
6) Fast photodiode with nd filter
59
59
Research Programme 3
Development of high-tech industrial
and scientific applications
Dr. Danijela Rostohar
Key R&D activities
Laser Induced Damage Threshold (LIDT)
LIDT station design
•ISO 21254 compliance
– Beam delivery system, beam monitoring, quality management: necessary components
needed to fulfill ISO requirements, also ensuring reproducibility and effectiveness of
measurements – crucial for effective cooperation with industry or research facilities.
•Vacuum chamber
– In order to isolate damage effect from atmospheric influences, it is recommended to
conduct LIDT measurements in vacuum. Here are major challenges to reduce organic
contaminants and ensure vacuum compliant devices for setup.
•Specimen diagnostics
– Core diagnostic relies on fast camera with proper optics system, capable both of damage
detection and base inspection of exposed specimen. Together with scattered light and
interference detection will be possible to effectively monitor online LIDT process for
repetition rates up to 2 kHz.
LIDT test station
Laser Shock Peening
Shock Peening
In the process of establishing cooperation with:
• Prof. Ocaña (Centro Láser UPM, Madrid, Spain)
• Dr. Alessandro Fortunato (Alma Mater University, Bologna )
• Dr. Alessandro Candiani (University of Parma)
“HiLASE multi-slab laser system:
a tool for efficient peening”
4th International Conference
on Laser Peening and Related
Phenomena Proc. Book, to be
published
Roman and Danijela visiting Prof. Ocaña - November 2013
Laser μ-nano processing station
20 µm holes
in metals
Carbon Reinforced Plastics (CRFP), ITO thin films, …
Cooperation with Industry
Laser vendors
- Process development
- Popularization of lasers
- Marketing
Laser end-users
- Safety training and education
- Process development
- Existing process improvement
HiLASE as a seed of…
Frederic Terman
Laser Valley ?
Fyzikální ústav AV ČR, v. v. i.
Na Slovance 2
182 21 Praha 8
hilase@fzu.cz
www.hilase.cz
www.hilase.cz/en
hilase@fzu.cz
Please, visit us on Facebook & Twitter, and be our FRIEND !
HiLASE: Nové lasery pro průmysl a výzkum
HiLASE (@hilaselasers)