{"id":9419,"date":"2022-08-10T07:47:55","date_gmt":"2022-08-10T07:47:55","guid":{"rendered":"https:\/\/www.szlaser.com\/?page_id=9419"},"modified":"2022-08-16T03:50:12","modified_gmt":"2022-08-16T03:50:12","slug":"ndyvo4-2","status":"publish","type":"page","link":"https:\/\/www.szlaser.com\/index.php\/wiki\/ndyvo4-2\/","title":{"rendered":"Brief Introduction to Nd:YVO4 Crystal"},"content":{"rendered":"

Brief Introduction to Nd:YVO4<\/span><\/a> Crystal from Physical and Optical<\/h1><\/h1><\/div>

Nd:YVO4<\/span><\/a> (neodymium-doped yttrium vanadate) crystal is a laser host crystal with excellent performance, suitable for making all-solid-state lasers pumped by laser diodes (LD). The crystal has the following characteristics: low laser threshold, high slope efficiency, large stimulated emission cross section, great absorption of pump light in a wide wavelength range, and single-mode tuning, high resistance to light damage. The latest progress shows that the combination of Nd:YVO4<\/span> <\/a>crystal and KTP<\/span><\/a> crystal can be used to make high-power stable infrared, green or red lasers.<\/p>\n<\/div>

# Physical and Optical Properties of Crystals<\/h1><\/div>

The Nd:YVO4<\/span><\/a> crystal belongs to the tetragonal system and is a positive uniaxial crystal. Nd:YVO4<\/span><\/a> crystal has been widely recognized as a very important laser material since its inception in 1966. However, the researchers found that such crystals have defects such as scattering centers and absorption color centers, making it impossible to grow high-quality crystals of sizes suitable for flashlamp pumping. Fortunately, it has great absorption and gain to the diode radiation wavelength, large emission cross-section, and good polarization characteristics of the output laser, which are enough to mask the shortcomings of its small growth size. Nd:YVO4<\/span><\/a> crystal is a laser crystal material with excellent performance that is very suitable for laser diode pumping.<\/p>\n

Some of its characteristic parameters are given below:
\nAbsorption wavelength (nm): 808.5;<\/p>\n

Absorption coefficient (cm-1): 31.4 (\u03c0 polarization, 808nm);
\nEmission wavelength (nm): 1064.3;<\/p>\n

Emission cross section (cm2): 25\u00d710-19 (1064nm);
\nFluorescence lifetime (\u03bcs): 94 (1.22at.%);<\/p>\n

Refractive index (@1064nm): no=1.957, ne=2.165;
\nThermal light coefficient (\/K, @300K): dno\/dT=8.5\u00d710-6, dne\/dT=3.0\u00d710-6<\/p>\n<\/div>

# Absorption and Divergence Properties of Crystals<\/h1><\/div>

Since this crystal is naturally birefringent, its absorption of the pump light is polarization dependent. If the polarization direction of the pump light is consistent with the laser radiation direction, the absorption of the pump light is the strongest. Figure 1(a) is the absorption spectrum of Nd:YVO4<\/span><\/a> crystal. It can be seen that the crystals exist between 800 and 900 nm<\/p>\n\n