Potassium Titanyl Phosphate (KTiOPO3 or KTP) Crystals are a versatile kind of optical crystals. The advantages of KTP crystals include high non-linear coefficient and damage threshold, wide acceptance angle, substantially temperature-stable phase-matching characteristics, and non-hygroscopicity. These traits, combined with its excellent transmission in the visible and near-IR wavelength range, have bulit up their prevalence in the field of Nonlinear Optics (NLOs).KTP crystals could be extensively utilized in the Second Harmonic Generation (SHG) of Nd:YAG lasers. When Shalom's KTP is applied outside the cavity of a 900mJ injection-seeded Q-switch Nd:YAG laser, the resultant output is a 700mJ green laser, suggesting a highly efficient conversion of over 80%. Other applications include OPO/OPA/OPG to obtain 600nm-4500nm light output and SFM. 

On the other hand, KTP crystals also manifest promising Electro-Optical properties, including great electro-optical coefficients and low dielectric constants, etc. Because KTP crystals virtually produce no parasitic oscillation, the crystals are attractive options for manufacturing EO modulators, Q-switches, EO deflectors, waveguides, etc.

Crysmit offers off-the-shelf and custom KTP Crystals with various coating options and rigorous QC inspection, and manifold apertures values up to 20x20mm are available. Standard coating options include: AR, HR, HT, PR dual-wavelength coatings for SHG, other custom coatings could also be tailored. For applications with higher power levels, High Gray Track Resistance (HGTR) KTP crystals are also procurable in Crysmit.

Applications KTP Crystals:

Second Harmonic Generation:

KTP crystals are especially the best media for the SHG of solid-state green lasers, which are currently becoming favored as pumping sources and amplifiers for visible dye lasers and tunable Ti: Sapphire lasers. With a 900mJ injection-seeded Q- switch Nd:YAG lasers using extra-cavity KTP, the resultant output would be 700mJ green laser, indicating a conversion efficiency above 80%. However, due to the susceptibility to gray-tracking of the crystals in high power operation, usually, the crystals are only applied when the power density is low/medium.

OPO, OPG, and OPA:

KTP is also used as a parametric source providing tunable output in the visible (600nm) to MIR (4500nm) wavelength range. One of the most favorable ways to accomplish extremely efficient conversion is to use tunable laser pumped non-critical phase-matched (NCPM) KTP OPO/OPA.  KTP OPO delivers steady continuous femtosecond pulses with a 108Hz repetition rate and milli-watt average power density, in both signal and idler outputs.

EO Modulations:

KTP possesses potential E-O and dielectric properties that are equivalent to LiNbO3, in addition to its distinctive NLO features. KTP's advantageous qualities make it ideal for a variety of E-O devices. The follow table is a comparison of KTP with other E-O modulator materials commonly used:

Applications for Optical Waveguides：

Based on the ion-exchange process on KTP substrate, low loss optical waveguides developed for KTP have created novel applications in integrated optics. Table 2 gives a comparison of KTP with other optical waveguide materials. Recently, a type Ⅱ SHG conversion efficiency of 20% /W/cm2 was achieved by the balanced phase matching, in which the phase mismatch from one section was balanced against a phase mismatch in the opposite sign from the second. Furthermore, segmented KTP waveguide have been applied to the type Ⅰ quasi-phase-matchable SHG of a tunable Ti:Sapphire laser in the range of 760-960 mm, and directly doubled diode lasers for the 400-430 nm outputs.Electro-Optic Waveguide Materials as follow:

Chemical and Structural Properties

Optical and Nonlinear Optical Properties