Home > Crystal   >  Nonlinear Crystal  >

Contact: *
Company: MSN/skype:
Tel: Fax:
E-mail: * Website:
Content: *
Code: *(marked *should be filled)

  Potassium Titanyl Phosphate (KTiOPO3 or KTP) crystals are widely used in both commercial and military lasers including laboratory and medical systems, range-finders, lidar, optical communication and industrial systems.
INFAST's KTP is featured by 
1. Large nonlinear optical coefficient
2.Wide angular bandwidth and small walk-off angle
3.Broad temperature and spectral bandwidth 
4. High electro-optic coefficient and low dielectric constant
5.Large figure of merit 
6.Nonhydroscopic, chemically and mechanically stable

INFAST offers 
1.Strict quality control
2.large crystal size up to 20x20x40mm3 and maximum length of 60mm;
3.Quick delivery(2 weeks for polished only, 3 weeks for coated)
4.Unbeatable price and quantity discount 
5.Technical support
6.AR-coating, mounting and re-polishing service

Chemical and Structural Properties of KTP Crystal

Crystal Structure

Orthorhombic, Space group   Pna21, Point group mm2.

Lattice Parameter

a=6.404 Å, b=10.616 Å,   c=12.814 Å

Melting Point  

~1172 °C

Mohs Hardness  



3.01 g·cm-3

Thermal   Conductivity 

13 W·m-1·K-1

Thermal Expansion   Coefficient

αx=11×10-6/K,   αy=9×10-6/K, αz=0.6×10-6/K

Optical and Nonlinear Optical Properties of KTP Crystal

Transparency Range

350 nm ~ 4500 nm

Thermo-optic Coefficient   [K-1](@1064nm)

dnx/dT=6.1×10-6    dny/dT=8.3×10-6   dnz/dT=14.5×10-6

Absorption    Coefficient

<0.1% cm-1   @1064nm    <1% cm-1 @532nm

For Type II SHG of
  a Nd:YAG laser @1064nm

Temperature Acceptance:   24 °C·cm-1
  Spectral Acceptance: 0.56 nm·cm-1
  Angular Acceptance: 14.2 mrad·cm-1 (φ);  55.3mrad·cm-1 (θ)
  Walk-off Angle: 0.55°

NLO Coefficients

deff(II)≈(d24-d15)sin2φsin2θ-(d15sin2φ   + d24cos2φ)sinθ

Non-vanished NLO   Susceptibilities [pm/V]

d31=6.5  d24=7.6    d32=5 pm/V   d15=6.1  d33=13.7

Sellmeier  Equations
  (λ in μm)   

  ny2=3.0333+0.04154/(λ 2-0.04547)-0.01408λ2
  nz2=3.3134+0.05694/(λ 2-0.05658)-0.01682λ2

Applications for SHG and SFG of Nd: lasers 
 KTP is the most commonly used material for frequency doubling of Nd:YAG and other Nd-doped lasers, particularly when the power density is at a low or medium level. To date, extra- and intra-cavity frequency doubled Nd:lasers using KTP have become a preferred pumping source for visible dye lasers and tunable Ti:Sapphire lasers as well as their amplifiers. They are also useful green sources for many research and industry applications. 
* More than 80% conversion efficiency and 700mJ green laser were obtained with a 900mJ injection-seeded Q-switch Nd:YAG lasers by using extra-cavity KTP.
* 8W green laser was generated from a 15W LD pumped Nd:YVO4 with intra-cavity KTP.
* 200mW green outputs are generated from 1 W LD pumped Nd:YVO4 lasers by using THATSHIGH's 2x2x5mm KTP and 3x3x1mm Nd:YVO4.
* 2-5mw green outputs are generated from 180mw LD pumped Nd:YVO4 and KTP glued  crystals. For more details, please refer to Glued Crystals.
KTP is also being used for intracavity mixing of 0.81μm diode and 1.064μm Nd:YAG laser to generate blue light and intracavity SHG of Nd:YAG or Nd:YAP lasers at 1.3μm to produce red light.

Applications for OPG, OPA and OPO 
As an efficient OPO crystal pumped by a Nd:laser and its second harmonics, KTP plays an important role for parametric sources for tunable outputs from visible (600nm) to mid-IR (4500nm), as shown in Fig. 3 and Fig. 4.
Generally, KTP's OPOs provide stable and continuous pulse outputs (signal and idler) in fs, with 108 Hz repetition rate and a mW average power level. A KTP’s OPO that are pumped by a 1064nm Nd:YAG laser has generated as high as above 66% efficiency for degenerately converting to 2120nm.The novel developed application is the non-critical phase-matched(NCPM) KTP OPO/OPA pumped by the X-cut KTP crystal. As shown in Fig.5, for pumping wavelength range from 0.7μm to 1 μm, the output can cover from 1.04μm to 1.45μm(signal) and from 2.15μm to 3.2μm(idler). More than 45% conversion efficiency was obtained with narrow output bandwidth and good beam quality.

Contact us
Tel: +86-(0)591 38206293
Fax: +86-(0)591 38206293
Official Social Media
Copyright © INFAST TECHNOLOGY(HK) LIMITED All Rights Reserved.