| YVO4
The yttrium orthovanadate (YVO4) is a positive uniaxial crystal grown with Czochralski method. It has good
mechanical and physical properties and is ideal
for optical polarizing components because of
its wide transparency range and large birefringence.
It is an excellent synthetic substitute for
Calcite (CaCO3) and Rutile (TiO2) crystals in many applications including fiber optic isolators
and circulators, beam displacers, Glan polarizers
and other polarizing optics, etc. |
 |
LiNbO3
LiNbO3 Crystal is widely used as frequency doublers for wavelength > 1mm and optical parametric
oscillators (OPOs) pumped at 1064 nm as well
as quasi-phase-matched (QPM) devices. Due to
its large Electro-Optic (E-O) and Acousto-Optic
(A-O) coefficients, LiNbO3 crystal is the most commonly used material for Pockel
Cells, Q-switches and phase modulators, waveguide
substrate, and surface acoustic wave (SAW) wafers,
etc. |
 |
| Nd:YAG
Nd:YAG crystal is the
most widely used solid-state laser material
today. GFE has recently expanded the crystal
growth facilities and production capability
for Nd:YAG crystals. In order to meet OEM and
R&D requirements, an improved quality assurance
procedure has been implemented in GFE during
the crystal growing and fabricating process. |
 |
| Nd:YVO4
Nd:YVO4
is one of the most efficient laser host crystal
currently existing for diode laser-pumped solid-state
lasers. Its large stimulated emission cross-section
at lasing wavelength, high absorption coefficient
and wide absorption bandwidth at pump wavelength,
high laser induced damage threshold as well
as good physical, optical and mechanical properties
make Nd:YVO4
an excellent crystal for high power, stable
and cost-effective diode pumped solid-state
lasers. Recent developments have shown that
Nd:YVO4
can produce powerful and stable IR, green, bule
lasers with the design of Nd:YVO4
and frequency doubling crystals. |
 |
| KTP
KTP has promising E-O and dielectric properties comparable to those of LiNbO3, which makes it extremely useful to various E-O devices. The
following Table gives the comparison of KTP
and those commonly used E-O modulator materials: |
 |
|
Material
|
1 |
|
Phase |
Amplitude |
| e |
n |
r
pm/V |
k
10-6/oC
|
n7r2/e
(pm/V)2
|
r
pm/v |
k
10-6/oC
|
n7r2/e(pm/V)2 |
|
KTP |
15.4 |
1.8 |
35 |
31 |
6130 |
27 |
11.7 |
3650 |
|
LiNbO3 |
27.9 |
2.2 |
31 |
82 |
7410 |
20.1 |
42 |
3500 |
|
KD*P |
48 |
1.47 |
26.4 |
9 |
178 |
24 |
8 |
178 |
|
LiIO3 |
5.9 |
1.74 |
6.4 |
24 |
335 |
1.2 |
15 |
124 |
|
| When
these properties are combined with high damage
threshold, low optical loss at high average
power, wide optical bandwidth, thermal and mechanical
stability, KTP crystals are expected to replace
LiNbO3 crystals as E-O modulators, especially
for mode-locking diode laser pumped Nd:YAG and
Nd:YLF lasers as well as Ti:Sapphire and Cr:LiSrAlF6
lasers. KTP crystal was successfully used to
mode lock a diode laser pumped Nd:YLF laser
at 270 MHz with pulse width of 15 ps and spectral
bandwidth of 73 GHz. |
BBO
High Temperature form BBO (a-BaB2O4) is a negative uniaxial crystal. It has
large birefringence over the broad transparent
range from 189 nm to 3500 nm. Recently, GFE
has succeeded in growing this crystal into large
size. The physical, chemical, thermal and optical
properties of a-BBO crystal are similar to those
of b-BBO. However, the nonlinear optical properties
of a-BBO crystal is vanished due to the centric
symmetry with its crystal structure. It is not
recommended to use for NLO processes. |
 |
