Descriptions:
KDP Potassium Dihydrogen Phosphate and KD*P or DKDP Potassium
Dideuterium Phosphate are one of the oldest used nonlinear materials. DKDP and KDP are known as
analogs, though their properties differ due to DKDP deuteration. They both
exhibit excellent ultraviolet transmission and high damage threshold. The
nonlinearity of these crystals is relatively low, these crystals can be grown
in large size. They found their application as nonlinear frequency doublers,
triplers, and quandruplers of Nd-doped lasers and as Q-switch devices for
Ti:Sapphire, Alexandrite, Nd-doped lasers. The main drawback is that these
crystals are highly hygroscopic, therefore sealed housing and dry operating
conditions have to be ensured.
Main
applications:
1） Laser
frequency conversion — harmonic generation for high pulse energy;
2） Electro-optical
modulation;
3） Q-switching
crystal for Pockels cells;
Advantages:
1)
Good
UV transmission;
2)
High
birefringence
3)
High
optical damage threshold;
4)
High
nonlinear coefficients;
5)
Non-hygroscopic,
chemically and mechanically stable
6)
Wide
working temperature range
7)
Low
capacitance
Basic properties
|
|
KDP
|
DKDP / KD*P
|
|
Chemical Formula
|
KH2PO4
|
KD2PO4
|
|
Transparency Range
|
200-1500nm
|
200-1600nm
|
|
Nonlinear Coefficients
|
d36=0.44pm/V
|
d36=0.40pm/V
|
|
Refractive index（@1064nm）
|
no=1.4938，ne=1.4599
|
no=1.4948，ne=1.4554
|
|
Electro-optical Coefficients
|
r41=8.8pm/V
r63=10.3pm/V
|
r41=8.8pm/V
r63=25pm/V
|
|
Longitudinal half-wave voltage
|
Vπ=7.65KV(λ=546nm)
|
Vπ=2.98KV(λ=546nm)
|
|
Absorptance
|
0.07/cm
|
0.006/cm
|
|
Optical damage threshold
|
＞5GW/cm2
|
＞3GW/cm2
|
|
Extinction ratio
|
|
30dB
|
|
Sellmeier equations of KDP (λ
in μm)
|
no2=2.259276+0.01008956/(λ2-0.012942625)+13.00522λ2/(λ2-400)
ne2=2.132668+0.008637494/(λ2-0.012281043)+3.2279924λ2/(λ2-400)
|
|
Sellmeier equations of KD*P (λ in μm)
|
no2=1.9575544+0.2901391λ2/(λ2-0.0281399)-0.02824391λ2+0.004977826λ4
ne2=1.5005779+0.6276034λ2/(λ2-0.0131558)-0.01054063λ2+0.002243821λ4
|
HGO offers KDP
or DKDP specifications:
|
Tolerance of cutting angle
|
△θ≤±0.25°,△φ≤±0.25°
|
|
Tolerance of dimension
|
Dimension+0/-0.1 mm，L：±0.1mm
|
|
Flatness
|
λ/10 @ 632.8nm
|
|
Wavefront distortion
|
λ/8@ 632.8nm
|
|
Surface quality
|
10/5 per MIL-O-13830A
|
|
Parallelism
|
20″
|
|
Perpendicularity
|
10′
|
|
Clear Aperture:
|
> 90%
|
|
Chamfer:
|
< 0.1 mm @ 45°
|
|
Size
|
Upon customer request
|
|
Coating
|
AR/HR coating upon customer’s request
|
|
Damage Threshold
|
750MW/CM2 at 1064nm, TEM00, 10ns, 10Hz
|
|
Quality Warranty Period
|
One
year under proper use
|
Why
Choose HGO ?
HGO supplies high
quality KDP and KD*P crystals for various applications. Because their polished
surfaces are easier to be moistened, the user is advised to provide the dry
condition (<50%) and the sealed housing for preservation. For this purpose, HGO
also provides polishing and sealed housing services for the KDP-based crystals.
Our engineers will serve you to select and design the best crystal, according
to the laser parameters you provide.
