|
Neodymium
doped Yttrium Aluminum Garnet (Nd:Y3Al5O12 or Nd:YAG)
crystal, which continues as the best of the rare earth garnet
materials that are characterized by four-level laser operation
which permits low threshold pulse and cw operation, is the most
mature and widely used solid-state laser material adopted by
R&D, medical, industrial and military customers. Its main
and obvious advantages are: high gain, low threshold, high efficiency,
low loss at 1.064 µm, as well as high optical quality, good
thermal conductivity and thermal shock characteristics, stable
chemical and mechanical properties, which make Nd:YAG as the
most suitable and commercial laser material for various modes
of operation (CW, pulsed, Q-switched, mode locked and cavity
dumped).
Erbium doped Yttrium Aluminum
Garnet (Er:Y3Al5O12 or Er:YAG) combine various output
wavelength with the superior thermal and optical properties
of YAG. It is a well known material for medical applications.
Ytterbium doped Yttrium Aluminum
Garnet (Yb:Y3Al5O12 or Yb:YAG) is one of the most promising
laser-active materials and more suitable for diode-pumping than
the traditional Nd-doped crystals. It can be pumped at 0.94
µm and generates 1.03 µm laser output. Compared with the commonly
used Nd:YAG crystal, Yb:YAG crystal has a larger absorption
bandwidth in order to reduce thermal management requirements
for diode lasers, a longer upper-state lifetime, three to four
times lower thermal loading per unit pump power. Yb:YAG crystal
is expected to replace Nd:YAG crystal for high power diode-pumped
lasers and other potential applications, such as, its doubling
wavelength is 515 nm very close to that of Ar-ion laser (514
nm), which makes it possible to replace large volume Ar-ion
laser.
<<<Back
|