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Potassium Titanyl Phosphate-KTP

Potassium Titanyl Phosphate (KTiOPO4 or KTP) was firstly reported in 1971. With the progress and improvement of KTP crystal growth technology, it is currently widely used in laser systems for industrial, military, laboratory, lidar and optical communication application.



KTP Features:

1.Large nonlinear optical coefficient

2.Large receiving angle and small departure angle

3.Wide temperature and spectral bandwidth

4.High photoelectric coefficient and low dielectric constant

5.High quality factor

6.Non deliquescent, stable in chemical and mechanical properties


Dimension Tolerance (W±0.1mm)x(H±0.1mm)x(L±0.2mm/0.1mm)
Clear Aperture ≥ 90%
Surface Quality (Scratch/Dig) 20/10
Angle Tolerance ≤0.250
Parallelism <30″
Perpendicularity ≤10′
Flatness <λ/8@633nm
Transmitted Wavefront Distortion <λ/8@633nm
Anti-Reflection Coating Customized

Chemical and Structural Properties

Crystal Structure Orthorhombic, Space group Pna21, Point group mm2
Lattice Parameter a = 6.404 Å, b = 10.616 Å, c = 12.814 Å, Z = 8
Melting Point About 1172℃
Mohs Hardness 5Mohs
Density 3.01g/cm3
Thermal Conductivity 13W/mK-1
Thermal Expansion Coefficients ax=11×10-6/℃, ay=9×10-6/℃, az=0.6×10-6/℃

Optical and Nonlinear Optical Properties

Transparency Range 350~4500nm
SHG Phase Matchable Range 497 ~ 1800nm  (Type II)
Therm-optic Coefficient ( λ in μm) dnx/dT=1.1X10-5/℃
Absorption Coefficients <0.1%/cm @ 1064nm    <1%/cm @ 532nm
For Type II SHG of a Nd:YAG laser at 1064nm Temperature Acceptance: 24℃·cm
Spectral Acceptance: 0.56nm·cm
Angular Acceptance: 14.2mrad·cm (φ);  55.3mrad·cm(θ)
Walk-off Angle: 0.55°
NLO Coefficients deff(II)≈(d24– d15)sin2φsin2θ- (d15sin2φ+ d24cos2φ)sinθ
Non-vanished NLO Susceptibilities d31=6.5 pm/V  d24=7.6 pm/V
d32= 5pm/V  d15=6.1 pm/V
d33=13.7 pm/V
Sellmeier Equations (λ in μm)[1] nx2=3.0065+0.03901/(λ2-0.04251)-0.01327λ2
ny2=3.0333+0.04154/( λ2-0.04547)-0.01408λ2
nz2=3.3134+0.05694/( λ2-0.05658)-0.01682λ2
Dielectric Constant ɛeff = 13

*[1] Reference to IEEE, J. Quantum Electronics, Vol.QE-27, No.5, 1137(1991)