KTP exhibits high optical quality, broad transparent range, relatively high effective SHG coefficient (about 3 times higher than that of KDP), rather high optical damage threshold, wide acceptance angle, small walk-off and type I and type II non-critical phase-matching (NCPM) in a wide wavelength range. 

KTP is the most commonly used material for frequency doubling of Nd:YAG lasers and other Nd-doped lasers, particularly at the low or medium power density. 

Advantages:

● Efficient frequency conversion(1064nm SHG conversion efficiency is about 80%)

● Large nonlinear optical coefficients(15 times that of KDP)

● Wide angular bandwidth and small walk-off angle

● Broad temperature and spectral bandwidth

● High thermal conductivity (2 times that of BNN crystal )

● Moisture free

● Minimum mismatch gradient

● Super-polished optical surface

● No decomposition below 900°C

● Mechanically stable 

● Low cost compare with BBO and LBO

Applications:

● Frequency Doubling (SHG) of Nd-doped Lasers for Green/Red Output

● Frequency Mixing (SFM) of Nd Laser and Diode Laser for Blue Output

● Parametric Sources (OPG, OPA and OPO) for 0.6mm-4.5mm Tunable Output

● Electrical Optical(E-O) Modulators, Optical Switches, and Directional Couplers

● Optical Waveguides for Integrated NLO and E-O Devices

Frequency Conversion:

KTP was first introduced as the NLO crystal for Nd doped laser systems with high conversion efficiency. Under certain conditions, the conversion efficiency was reported to 80%, which leaves other NLO crystals far behind.

Recently, with the development of laser diodes, KTP is widely used as SHG devices in diode pumped Nd:YVO4 solid laser systems to output green laser, and also to make the laser system very compact.

KTP for OPA, OPO Applications:

In addition to its wide use as a frequency doubling device in Nd-doped laser systems for Green/Red output, KTP is also one of the most important crystals in parametric sources for tunable output from visible (600nm) to mid-IR (4500nm) due to the popularity of its pumped sources, the fundamental and second harmonic of a Nd:YAG or Nd:YLF lasers.

One of the most useful applications is the non-critical phase-matched (NCPM) KTP OPO/OPA pumped by the tunable lasers to obtain a high conversion efficiency.KTP OPO results in stable continuous outputs of femto-second pulse of 108 Hz repetition rate and milli-watt average power levels in both signal and idler outputs.

Pumped by Nd-doped lasers, KTP OPO has obtained above 66% conversion efficiency for down-conversion from 1060nm to 2120nm.

Electro-Optical modulators:

KTP crystal can be used as electro-optical modulators. For more information, please contact our sales engineers.