YAG, or yttrium aluminum garnet, is a common laser active crystal that is widely used in a variety of laser systems. YAG has a crystalline structure that allows it to amplify light through the process of stimulated emission. When YAG is excited by an external energy source, such as a flash lamp or diode, it emits light at a specific wavelength determined by the crystal's properties.
One of the primary advantages of YAG as a laser active crystal is its high thermal conductivity, which allows it to dissipate heat efficiently and operate at high power levels without damage. YAG also has a broad emission spectrum that can be tailored to specific applications by doping the crystal with different ions, such as neodymium or erbium.
Nd:YAG, or neodymium-doped YAG, is one of the most common types of YAG lasers. Nd:YAG lasers are used in a wide range of applications, including industrial cutting and welding, medical procedures, and scientific research. They emit light at a wavelength of 1064 nanometers, which is in the infrared part of the spectrum.
YAG crystals are also used in other types of lasers, such as Er:YAG (erbium-doped YAG) lasers, which emit light in the mid-infrared range, and Ho:YAG (holmium-doped YAG) lasers, which emit light at a wavelength of 2097 nanometers.
|Dopant concentration, at.%||0.7 - 1.1||up to 50||LOW: 6 - 8%, HIGH: 20%|
|Thermal expansion coefficient||7.8 x 10-6 x °K-1, <111> |
8.2 x 10-6 x °K-1, <100>
|9,5 x 10-6 K-1 (a axis), 4,3 x 10-6 K-1 (b axis), |
10,8 x 10-6 K-1 (c axis)
|7.8 x 10-6 x °K-1, <111>, 0 - 250 °C|
|Thermal conductivity at 25°C, W x cm-1 x °K-1||0.14||0.12||0.14|
|Loss coefficient at 1064 nm, cm-1||0.003||0.003||0.003|
|Refractive index, at 1 µm||1.82||1.837||1.82|
|Lasing wavelength, nm||1064.0||2940||1030|
Rods with round cross-sections are manufactured:
|Diameter, mm||(4 ÷ 8) ± 0.025|
|Length, mm||up to 130 ± 0.5|
|Parallelism, arc sec||< 10|
|Perpendicularity, arc min||< 10|
|Roughness, scratch/dig||10 - 5|