Yttrium Vanadate (YVO4) Crystal

-----A Birefrigent Crystal For Fiber Optics

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.

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 D4h
Crystal Cell a=b=7.12Å; c=6.29Å
Density: 4.22 g/cm3
Hygroscopic Susceptibility: Non-hygroscopic
Mohs Hardness: 5, glass-like
Thermal Expansion Coefficient aa = 4.43 x 10-6/K; ac = 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 no=na=nb, ne=nc
Refractive Indices, Birefringence ( Dn = ne - no) and Walk-off Angle at 45¡ã (r): no = 1.9929, ne = 2.2154, Dn = 0.2225, r = 6.04¡ã at 0.63 mm no = 1.9500, ne = 2.1554, Dn = 0.2054, r = 5.72¡ã at 1.30 mm no = 1.9447, ne = 2.1486, Dn = 0.2039, r= 5.69¡ã 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: dna/dT = 8.5x10-6/K; dnc/dT = 3.0x10-6/K

Comparation with other Birefringent crystals

tCompared 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.

tCompared 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.

tCompared to LiNbO3, although they have similar mechanical and physical properties, YVO4 has more than three times larger birefringence, that makes your design more compact.

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.

YVO4 Beam Displacer

Specifications

Note: Other sizes and specifications are available upon request

Standard Size

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