Date: 11 Nov, 2022
The nonlinear optical crystal is the crystal which shows the nonlinear optical impact greater than two times for the laser electrical field. Nonlinear optical crystal is a sort of useful material, in which the frequency-doubling (or “frequency conversion”) crystal can be used to convert the laser wavelength, so as to extend the tunable variety of the laser, which has vital application worth in the field of laser technology.
There are hundreds of various type of nonlinear crystals, Common lithium niobate (LiNbO3 – LN), lithium tantalate (LiTaO3 – LT), potassium dihydrogen phosphate (KH2PO4 – KDP), potassium dideuterium phosphate (KD2PO4 – DKDP), lithium iodate (LiIO3 – LI), potassium titanium phosphate (KTiOPO4 – KTP), barium metaborate (BaB2O4 – BBO), lithium trisborate (LiB3O5 – LBO), potassium niobate (KNbO3 – KN), potassium beryllium fluorborate (KBe2BO3F2 – KBBF), cesium borate (CSB3O5 – CBO), cadmium selenide CdSe, Gallium selenide GaSe, cesium lithium borate (LiCSB6O10 – CLBO), silver thiogas (AgGaS2 – AGS), silver selenium gallium (AgGaSe2 – AGSe, arsenic-cadmium germanium (CDGEAS – CGA), phospho-germanium zinc (ZnGEP2 – ZGP) are widely utilized in laser frequency increasing, amount frequency, distinction regularity, optical parametric boosting, electro-optic inflection, electro-optic deflection, etc.
Also Read About: Diffusion Bonding Crystal
In this Article
For nonlinear optical crystals, along with having large effective nonlinear coefficients, the complying with residential or commercial properties are also called for:
Here are some examples of usual nonlinear optical crystals
BBO crystal is acknowledged as one of the most outstanding second-order nonlinear optical crystal in the world. Among its exceptional features is its large frequency inflection range. A lot more importantly, by utilizing its regularity down-conversion procedure, BBO crystal can be made into a continually tunable completely healed tuned laser with wavelength from visible to near-infrared.
Barium borate (BBO) has large birefringence and also reduced dispersion, high damages threshold, vast phase matching range, great temperature level security, big nonlinear optical impact, and the regularity increasing coefficient is 6 times that of KDP crystal. It has a very variety of pervious to light, reduced absorption coefficient, the weaker the piezoelectric buzzing effect, about other crystal electro-optic inflection, has higher extinction ratio, the bigger stage in a sustaining duty, high optical damages limit, the temperature of the broadband matching, and also exceptional optical homogeneity and to improve the laser output power stability, Specifically for the triple regularity Nd: YAG laser has a large range of applications.
Lithium trisborate, additionally referred to as LBO, is an outstanding high-power UV frequency-doubling crystal with broad transmittance band, high damages limit and also large acceptance Angle. Lithium trisborate (LiB3O5, referred to as LBO) crystal is frequently used in center and also high power 1064nm double as well as three-way regularity lasers.
It has really high light damages resistance threshold, great light uniformity, wide obtaining Angle, excellent mechanical residential properties, strong thermal shock resistance, microdelixation, as well as huge nonlinear coefficient. It is among the nonlinear crystals with superb comprehensive residential or commercial properties. The biggest advantage of LBO is that it can make use of temperature adjusting to achieve non-critical phase matching (NCPM). When the regularity doubling process pleases the non-critical phase matching relationship, the separation Angle in between the basic frequency and the 2nd harmonic of the frequency increasing is 0. Currently, the reliable length of the LBO crystal can theoretically reach infinity, which can make up for its small nonlinear coefficient. Due to its big damage limit, this indicates that high-power essential wave pumping can be achieved.
Compared to LiNbO3 crystal, MgO: LiNbO3 crystal has its distinct benefits in the application of NCPM regularity doubling, blending as well as optical parametric oscillation in Nd-doped lasers.
The anti-damage limit of doped MgO: LiNbO3 crystal is more than twice more than that of pure LiNbO3 crystal.