Page 1
Daniel Rytz, Andreas Gross, Sophie Vernay, Volker Wesemann
F.E.E. GmbH, Struthstrasse 2, D-55743 Idar-Oberstein
Remerciements:
X. Pétrissans, J. Lejay, L. Georghe, P. Loiseau, G. Aka
Lab. de Chimie de la Matière Condensée, UMR 7574, ENSCP
P. Georges1, A. Maillard2, Ph. Villeval3, L. McDonagh4, F. Salin4
1- Lab. Charles Fabry, Institut d‘Optique
2-LMOPS, CNRS-UMR 7132, Univ. de Metz et Supelec
3-Cristal Laser
4-Eolite
CMDO 24.11.08
CRISTAUX DE YAB = YAl3(BO3)4 POUR
CONVERSION DE FREQUENCE DANS L’UV
Page 2
PLAN
• Cristaux non linéaires pour l‘UV.
• Limites des cristaux existants
THG 355 nm, SHG 266 nm.
• Propriétés du YAB:
– SHG, THG, SFG.
– Etat de l‘art et perspectives.
Page 3
Pump Nd:YAG SHG THG UV output
808 nm 1064 nm 532 nm 355 nm
NLO CRYSTALS FOR UV (340-360 nm)
Pump Yb:Y2O3 SHG THG UV output
946 nm 1030 nm 515 nm 343 nm
Pump Pr:YLF SHG
405 nm 720 nm 360 nm
Page 4
Pump Nd:YAG SHG SHG UV output
808 nm 1064 nm 532 nm 266 nm
NLO CRYSTALS FOR UV (250-270 nm)
Pump Yb:Y2O3 SHG SHG UV output
946 nm 1030 nm 515 nm 257 nm
Pump Pr:YLF SHG
405 nm 510 nm 255 nm
Page 5
NEW NL MATERIAL
FOR UV GENERATION
• Motivation:
generation of wavelengths < 450 nm.
• Wanted:
0,326 – 0,366 µm (HG of Nd3+, Yb3+).
0,245 – 0,275 µm (HG of Nd3+, Yb3+).
0,245 – 0,365 µm (HG of Pr3+).
• State of the art presently limited to very few NL
materials.
Page 6
MATERIALS FOR SFG 355 nm
1,10,523,133,7BiBO
8-103,3
2,1
0,9
0,4
58,7
73,2
YCOB
63,83,150,80,6842,737LBO
13160,350,261,42,053931BBO
II
T acc
(°C cm)
I
T acc
(°C cm)
II
Ang acc
mradcm
I
Ang acc
mradcm
II
deff
(pm/V)
I
deff
(pm/V)
Type II
angle
Type I
angle
1064 nm 532 nm 355 nm
Page 7
MATERIALS FOR SHG 266 nm
3,20,430,6136,2KBBF
KBe2BO3F2
2,50,340,2655KABO
K2Al2B2O7
1,96,20,490,861,5CLBO
CsLiB6O10
4,850,171,147,5BBO
BaB2O4
Walk-off
(°)
T acc
(°C cm)
Ang acc
mradcm
deff
(pm/V)
Type I
angle
532 nm 266 nm
Page 8
LIMITATIONS
• BBO - hygroscopic.
- angular acceptance and walk-off.
• LBO - hygroscopic.
- SHG only for > 555 nm.
• YCOB - limited deff.
- SHG only for > 720 nm.
Page 9
LIMITATIONS (Cont‘d)
• CLBO - strongly hygroscopic.
• BiBO - absorption below 290 nm.
• KBBF - contains Beryllium.
Page 10
NL MATERIALS FOR UV
There is a need to find a material with a
favorable set of properties:
- not hygroscopic.
- non toxic.
- phase matchable with acceptable deff.
- low losses.
- high damage threshold.
Page 11
Trigonal
Hardness 7.5 mohs
Not hygroscopic
Thermal conductivity 3 - 4 W m-1 K-1
Transmissive 160 – 2200 nm
Where is UV cutoff in transmission?
NEW UV MATERIAL (PROPOSED: JULY 2007)
Page 12
(RE)Al3(BO3)4 (with RE=rare earth),
YAB = YAl3(BO3)4,
LuAB = LuAl3(BO3)4,
YbAB = YbAl3(BO3)4,
GAB = GdAl3(BO3)4.
Page 13
SHG Angle vs. Fundamental
0,00
10,00
20,00
30,00
40,00
50,00
60,00
70,00
80,00
90,00
0 0,5 1 1,5 2 2,5
Wavelength (µm)
Ph
ase m
atc
hin
g a
ng
le (
°)
Type I
Type II
λ λ/2
Page 14
SHG Nonlinearity
SHG: effective nonlinear coefficients
0,000
0,200
0,400
0,600
0,800
1,000
1,200
1,400
1,600
0 0,5 1 1,5 2 2,5
Fundamental wavelength (µm)
NL
co
eff
icie
nt
(pm
/V)
Type I (Phi = 0°)
Type II (Phi = 30°)
Page 15
SHG Parameters
Tab. 5 SHG Typ I Typ II Typ I Typ II Typ I Typ II Typ I
Phi = 0° Phi=30°
Winkel-
akzeptanz
Winkel-
akzeptanz
Walk-
off
Lambda Lambda/2 Winkel Winkel deff deff mrad cm mrad cm °
µm µm ° ° pm/V pm/V
0,492 0,246 85,4 0,14 1,76 0,42
0,502 0,251 77,1 0,38 0,66 1,13
0,532 0,266 66,2 0,69 0,41 1,91
0,622 0,311 51,1 1,07 0,36 2,52
0,742 0,371 41,2 65,6 1,28 0,29 0,43 1,09 2,54
0,802 0,401 38,1 58,3 1,34 0,47 0,47 0,99 2,48
0,912 0,456 34,0 50,3 1,41 0,69 0,56 1,03 2,36
Page 16
THG Angle vs. Wavelength
0,00
10,00
20,00
30,00
40,00
50,00
60,00
70,00
80,00
90,00
0 0,5 1 1,5 2 2,5
Wavelength (µm)
Ph
ase m
atc
hin
g a
ng
le (
°)
Type I
Type II
λ and λ/2 λ/3
Page 17
THG Nonlinearity
THG: effective nonlinear coefficients
0,000
0,200
0,400
0,600
0,800
1,000
1,200
1,400
1,600
0 0,5 1 1,5 2 2,5
Fundamental wavelength (µm)
NL
co
eff
icie
nt
(pm
/V)
Type I (Phi = 0°)
Type II (Phi = 30°)
Page 18
THG Parameters
THG Typ I Typ II Typ I Typ II Typ I Typ II
Phi=0
°
Phi=30
°
Winkel-
akzeptanz
Winkel-
akzeptanz
Lambda 1 Lambda 2 Lambda 3 Winkel Winkel deff deff
µm µm µm ° ° pm/V pm/V mrad cm mrad cm
0,710 0,355 0,237 79,8 0,30 0,74
0,810 0,405 0,270 58,4 0,89 0,33
0,950 0,475 0,317 46,5 60,3 1,17 0,42 0,35 0,58
1,030 0,515 0,343 42,3 53,6 1,26 0,60 0,38 0,57
1,060 0,530 0,353 41,0 51,6 1,28 0,66 0,40 0,58
1,340 0,670 0,447 33,2 40,7 1,42 0,98 0,55 0,72
Page 19
SFG Parameters
SFG Typ I Typ II Typ II Typ I Typ II Typ I Typ II
ooe eoe
oee
Phi=0
° Phi=30°
Winkel-
akzeptanz
Winkel-
akzeptanz
Lambda 1 Lambda 2 Lambda 3 Winkel Winkel Winkel deff deff
µm µm µm ° ° ° pm/V pm/V mrad cm mrad cm
1,344 0,881 0,532 30,5 39,2 51,7 1,47 1,02 0,70 0,98-1,55
1,554 0,809 0,532 30,2 36,8 57,0 1,47 1,09 0,70 0,91-1,92
0,810 0,632 0,355 42,9 62,6 1,25 0,36 0,40 0,85
1,064 0,532 0,355 40,8 51,5 1,29 0,66 0,40 0,59
0,642 0,454 0,266 64,5 0,73 0,38
0,722 0,421 0,266 62,2 0,79 0,35
0,812 0,396 0,266 59,6 0,86 0,33
0,982 0,365 0,266 55,1 70,0 0,97 0,20 0,31 0,59
1,062 0,355 0,266 53,3 64,9 1,02 0,31 0,30 0,48
1,342 0,332 0,266 48,0 54,4 1,14 0,58 0,28 0,36
Page 20
SFG Parameters (cont‘d)
SFG Typ I Typ II Typ II Typ I Typ II Typ I Typ II
ooe eoe
oee
Phi=0
° Phi=30°
Winkel-
akzeptanz
Winkel-
akzeptanz
Lambda 1 Lambda 2 Lambda 3 Winkel Winkel Winkel deff deff
µm µm µm ° ° ° pm/V pm/V mrad cm mrad cm
1,064 0,266 0,213 72,1 0,52 0,37
1,326 0,254 0,213 61,5 69,9 0,81 0,20 0,26 0,38
0,720 0,355 0,238 77,8 0,36 0,62
0,720 0,520 0,302 52,4 1,04 0,35
0,910 0,720 0,402 37,7 53,0 64,2 1,35 0,62 0,47 0,82-1,29
0,910 0,808 0,428 35,8 51,5 56,3 1,38 0,66 0,51 0,91-1,09
1,064 0,532 0,355 40,8 51,4 1,29 0,66 0,40 0,59
1,062 0,589 0,379 38,7 49,5 1,33 0,72 0,43 0,65-1,35
1,062 0,751 0,440 34,6 46,2 59,5 1,40 0,81 0,53 0,82-1,26
1,062 0,808 0,459 33,6 45,6 55,2 1,42 0,83 0,56 0,89-1,72
1,338 0,749 0,480 32,0 39,9 59,7 1,44 1,00 0,61 0,83-1,21
1,338 0,806 0,503 31,2 39,5 55,6 1,45 1,01 0,65 0,89
Page 21
SFG or OPO Angles
SFG OR OPO WITH 355 nm PUMP
30,00
40,00
50,00
60,00
70,00
80,00
90,00
0 0,5 1 1,5 2 2,5
Wavelength (µm)
Ph
ase m
atc
hin
g a
ng
le (
°)
ooe
eoe
ooe
eoe
oee
oee
Page 22
PROPERTIES OF (RE)ABStructure Trigonal, space group R32
Lattice parameters a = 9.287 A (GAB: 9.34 A; LuAB: -)
c = 7.256 A (GAB: 7.31 A; LuAB: -)
Density 3. 70 g/cm3
Melting noncongruent
Hardness Mohs 7.5
Stability non hygroscopic
Specific heat 0.75 W s g-1 K-1
Thermal coductivity 3 – 4 W m-1 K-1
Transmission 160 – 2200 nm
Indices no = 1.7553 (GAB: 1,761, at 1064 nm)
ne = 1.6869 (GAB: 1,689, at 1064 nm)
Uniaxial negative (no > ne)
Page 23
(RE)AB AND YAB IN THE
LITERATURE
• Large number of references on
Nd:YAB
Nd:GAB
Yb:YAB
since 1981.
• Mostly for self-doubling.
• Only limited work on undoped (RE)AB.
Page 24
PAST WORK ON UNDOPED
(RE)AB
US Patent 5‘030‘851
(Filed 1990, expired 1994)
YAB (without Nd) as a NLO crystal.
SHG 1064/532 nm Type I reported.
Angle =33° from z to x in xz plane.
(Should be corrected, theta = 30.8°, phi = 0°).
Speculation about NCPM.
Page 25
PAST WORK ON UNDOPED
(RE)AB
US Application 2006/0054864
YAB with less than 1000 ppm Mo
for generation of wavelengths < 350 nm.
SHG 532/266 nm observed,
no details provided.
Page 26
COMPARISON
Present work: Based on Luo et al. (1989):
0,00
10,00
20,00
30,00
40,00
50,00
60,00
70,00
80,00
90,00
0 0,5 1 1,5 2 2,5
Wavelength (µm)
Ph
ase m
atc
hin
g a
ng
le (
°)
Type I
Type II
0,00
10,00
20,00
30,00
40,00
50,00
60,00
70,00
80,00
90,00
0 0,5 1 1,5 2 2,5
W ave le ngth (µm )
Ph
ase m
atc
hin
g a
ng
le (
°)
Type I
Type II
Page 27
SUMMARY OF NLO
PROPERTIES
1,9Approx.
6
0,410,6966,2YAB
1,96,20,490,861,5CLBO
4,850,171,147,5BBO
Walk-
off
(°)
T acc
(°C cm)
Ang acc
mradcm
deff
(pm/V)
Type I
Angle
SHG
532/266
nm
Page 28
SUMMARY (cont‘d)
0,580,400,661,2851,641,0YAB
1,10,523,133,7BiBO
8-103,3
2,1
0,9
0,4
58,7
73,2
YCOB
63,83,150,80,6842,737LBO
13160,350,261,42,053931BBO
II
T acc
(°C cm)
I
T acc
(°C cm)
II
Ang acc
mradcm
I
Ang acc
mradcm
II
deff
(pm/V)
I
deff
(pm/V)
Type
II
angle
Type
I
angle
THG
355
nm
Page 29
OUTLOOK AND FUTURE
WORK
• YAB, LuAB, YbAB, GdAB are promising
materials for UV generation.
• Phase matching conditions known and
verified for several wavelenths.
• Challenge: crystal growth of high purity
(low loss in UV range) material.
• Damage threshold ? Light induced effects?