Nd: YVO4 crystal belongs to the tetragonal system, positive uniaxial crystal. Nd: YVO4 crystal has been extensively identified as an important laser material, given its development in 1966.
Nonetheless, the researchers discovered problems in the scattering center, absorption color center, etc. It is, consequently, difficult to grow high-quality crystals of the size needed for a flash pump.
Thankfully, it has superb absorption and gains to the wavelength of diode radiation. And the transmission area is huge. The output laser has great polarization features. These are enough to cover the drawbacks of its tiny development dimension.
Advantages
Nd: YVO4 crystal has superb properties. Compared with another commonly utilized Nd: YAG crystal (neodymium-doped yttrium aluminum garnet crystal), its pump broadband is much more extensive. The absorption bandwidth performance is greater. The boosted exhaust cross-section is more comprehensive and has exceptional advancement value. Nd: YVO4 crystals are used in conjunction with nonlinear optical crystals such as LBO crystals, BBO crystals, KTP crystals, etc. It can achieve frequency-doubling conversion as well as change working wavelength. The all-solid-state laser made from Nd: YVO4 crystal can result from near-infrared light, green light, blue light, ultraviolet light, and so on.
- Concerning 808 nm pump transmission capacity, regarding the Nd: YAG 5 times.
- The area at 1064 nm of the boosted exhaust of radiation is an Nd: YAG three times.
- The light damage threshold is low, with a high slope efficiency.
- Uniaxial crystal axis, the outcome of linear polarization.
Weaknesses
Compared with the traditional Nd: YAG crystal, Nd: YVO4 has the advantages of a much more significant absorption coefficient, greater emission random sample, polarization absorption as well as emission characteristics, larger absorption transmission capacity, as well as insensitivity to the temperature level modification of the diode. Consequently, it is widely used in LD-pumped solid-state lasers.
It has a big discharge cross-section and a brief top power lifetime. The power storage ability of Nd: YVO4 is much less than that of Nd: YAG. Not for high power, peak power of the Q – switched over pulse output. Their benefits are restricted to continuous wave results, ordinary high control, and high conversion effectiveness. In addition, the thermal conductivity of Nd: YVO4 is small, only fifty percent of that of Nd: YAG. Therefore, it is not conducive to attaining high-power continuous wave output.
Apply
Neodymium-doped yttrium vanadate (Nd: YVO4) crystal is a type of laser crystal with excellent efficiency, which is suitable for producing a laser diode pump, specifically a low-power laser. Compared with Nd: YAG, Nd: YVO4 has a greater absorption coefficient and a larger promoted emission cross-section.
Laser diode-pumped Nd: YVO4 crystals are incorporated with LBO, BBO, KTP, and other crystals with high nonlinear coefficients. It can achieve better frequency-doubling conversion performance. It can result in near-infrared, green, and blue ultraviolet and solid-state lasers.
Nd: YVO4 crystals can commonly be used in optical interaction, industrial laser handling, laser ranging, semiconductor discovery, information storage, screen, laser printing, medical examination, equipment, clinical research, and other areas.
Additionally, Nd: YVO4 diode-pumped solid-state lasers are quickly changing traditional water-cooled ion lasers and lamp-pumped lasers on the market, specifically in miniaturization as well as single longitudinal mode outcome.
In the 21st century, several downstream markets of Nd: YVO4 crystal is booming, and the application variety of Nd: YVO4 crystal is regularly increasing with obvious performance benefits.
Growth method.
In the 1960s, Nd: YVO4 crystal was developed. It was removed from salt metavanadate melt by the air conditioning approach. The dimension of the Nd: YVO4 crystal expanded by this technique was small. Ever since, the growth procedure of Nd: YVO4 crystal has been put forward, such as the Zhilar method, flame melting method, floating zone development method, Bryman method, and pull method. At present, the growth methods of Nd: YVO4 crystal are various. The illustration technique is the mainstream Nd: YVO4 crystal growth process, which can grow big, top-notch crystals.
Pulling method.
Nd3+: YVO4, crystal melting point is high (1820 ℃), must use gold-dependent crucible growth, gold-dependent crucible will certainly be oxidized at heat, must make use of a neutral gas (hydrogen) to protect the crucible.
By growing in an anoxic environment, the dissolved part will certainly decompose into inexpensive vanadium oxide (part of YVO4 will break down into YVO3), and oxygen deficiency will happen in the crystal, resulting in the generation of the color center.
Growing in an oxygen-rich atmosphere will cause extreme oxidation of the crucible. The minimized episcopes create additions inside the crystal. This will lead to strong melt volatilization, resulting in component deviation.
By utilizing different growing environments in various stages, the oxygen deficiency in the crystal can be supplemented, the volatilization of resources can be inhibited, the single-phase growth of the crystal can be assured, and the crystal can not be smudged or spread because of oxygen deficiency because of hypoxia.
