Yttrium Vanadate (YVO4) Crystal

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.

1.Basic Properties of YVO4 crystals

Transparency Range high transmittance from 0.4 to 5mm	Transparency Curve of YVO4(Thickness=1mm)
Crystal Symmetry Zircon Tetragonal, space group D_4h
Crystal Cell a=b=7.12 Å; c=6.29 Å
Density: 4.22 g/cm³
Hygroscopic Susceptibility: Non-hygroscopic
Thermal Expansion Coefficient a_a = 4.43 x 10^-6/K; a_c = 11.37 x 10^-6/K
Thermal Conductivity Coefficient \|\|C: 5.23 W/m/K; ^ C: 5.10 W/m/K
Crystal Class: Positive uniaxial with n_o=n_a=n_b, n_e=n_c
Refractive Indices, Birefringence (Dn = n_e - n_o) and Walk-off Angle at 45^º (r): n_o = 1. 9929, n_e = 2.2154, Dn = 0.2225, r = 6.04 at 0.63 mm n_o = 1.9500, n_e = 2.1554, Dn = 0.2054, r = 5.72 at 1.30 mm n_o = 1.9447, n_e = 2.1486, Dn = 0.2039, r = 5.69 at 1.55 mm
Sellmeier Equation (l in mm): no2= 3.77834 + 0.069736/(l² - 0.04724) - 0.0108133l² ne2=4.59905 + 0.110534/(l² - 0.04813) - 0.0122676l²
Thermal Optical Coefficient: dn_a/dT = 8.5x10^-6/K; dn_c/dT = 3.0x10^-6/K

2.Comparation with other Birefringent crystals

Compared to Calcite, YVO4 has better temperature stability and physical and mechnical properties. Calcite is hard to obtain high optical quality because of its low susceptibility to moisture and low hardness.
Compared to Rutile (TiO2) which exhibits too high hardness, YVO4 is easier to be handled for optical surface processing that greatly reduces cost of fabrication, especially for batch production.
Compared to LiNbO3, although they have similar mechanical and physical properties, YVO4 has more than three times larger birefringence, that makes your design more compact.

3.Applications of YVO4 Crystals

Following drawings are the simple demonstrations of how the YVO4 crystals are used in Fiber Optic Isolator, Beam Displacers and Circulators.

CASTON unique advantages:

Reliable OEM supplier: CASTON has the largest production line of YVO4 crystals in the world. We have capacity to fabricate up to 10,000 pieces of YVO4 components per month.
Strong Technical Support: From crystals growth and fabrication to fiber optics design and applications, CASTON engineers always provide professional solution to customers. Come to CASTON , let our expertise serves you better.
Quick Delivery: We offer a series of standard YVO4 components which are commonly used in fiber optics . They are available off-the-shelf.
Special Products: Custom-made YVO4 components are welcome.

1. Birefringent Wedges for Fiber-Optic Isolators

Aperture	1.0 x 1.0 mm² to 2 x 2 mm²	specifications
Dimension tolerance	+/-0.05mm
Wedge Angle tolerance	+/-15%
Optical axis orientation	+/-0.5°
Flatness	l/4 @ 632.8 nm
Surface Quality	20-10
AR-coating	R<0.2% @1550nm

Note: Other sizes and Coating are available upon request

2. YVO4 Beam Displacer

Dimension tolerance:± 0.05 x ± 0.05 x ± 0.1mm	Specifications
Optical axis orientation: +/-0.5°
Parallelism: <15 arc sec
Perpendicularity: <10 arc min
Flatness: l /4 @ 632.8 nm
Surface Quality: 20-10
AR-coating: R<0.2% @ 1550 nm± 40 nm

Note: Other sizes and specifications are available upon request