KTP nonlinear crystals are mainly used for frequency doubling in solid-state Nd:YAG or Nd:YVO₄ lasers, owing to their large nonlinear optical coefficient, wide bandwidth, small walk-off angle, and broad temperature and spectral bandwidth. KTP crystals also feature a high electro-optic (EO) coefficient, low dielectric constant, and high figure of merit, making them widely used in electro-optic applications.

KTP (KTiOPO₄) is a nonlinear optical crystal with excellent nonlinear and electro-optic properties, including a large nonlinear optical coefficient, wide bandwidth, and small walk-off angle, making it suitable for various nonlinear frequency conversion applications.

With high effective nonlinearity (d_eff ≈ 8.3 × d₃₆(KDP) at 1.06 μm) and outstanding optical performance, KTP is an ideal laser material. The phase-matching range of KTP crystals covers the 0.99–3.3 μm region. KTP can be used for intracavity and extracavity frequency doubling of the most common lasers such as Nd:YAG, Nd:Glass, and Nd:YLF.