Some specific optical parameters of neodymium-doped yttrium aluminum garnet (Nd:YAG) crystals: 

1.Absorption spectrum 

Main absorption peak: It is located at a wavelength of 808 nm. This is a typical absorption peak of Nd³⁺ ions and is commonly used in solid - state lasers pumped by laser diodes (LDs) [1].

Absorption coefficient: When the Nd doping concentration is 0.030 mole fraction (mol%), the absorption coefficient is as high as 20.7 cm⁻¹, indicating a relatively high absorption efficiency for 808 - nm light [1].

Fluorescence characteristics 

2.Fluorescence lifetime: At a relatively high doping concentration (e.g., 0.030 mol%), the fluorescence lifetime is 150 μs. The lifetime may be shortened due to the concentration quenching effect [1].

Emission wavelength: The main emission wavelength is 1064 nm (near - infrared band), which is a characteristic of the four - level laser transition of Nd³⁺ ions and is suitable for high - efficiency laser output. 

3.Optical uniformity

Nd:YAG crystals are well - known for their good optical uniformity. They are suitable for high - power laser applications and can suppress scattering and mode distortion [2][3]. 

4.Thermal and mechanical properties 

Thermal conductivity: It is relatively high (the specific value is not clear, but it is better than most laser crystals), which helps to alleviate the thermal effect under high power [2].

Mechanical properties: They have high hardness and high stability, making them suitable for extreme environments (such as military and industrial processing) [2][3]. 

5.Influence of doping concentration

The doping concentration range is usually 0.6%–1.4% (by mass). An excessively high concentration may lead to concentration quenching and reduce the fluorescence efficiency or laser performance [1].