α-BBO Crystal
α-BBO (α-BaB2O4) is a negative uniaxial crystal which has large birefringence over a broad transparent range of 190nm to 3500nm.α-BBO is an excellent crystal especially in UV and high power
applications. The physical, chemical, thermal and optical properties of α-BBO crystal are similar to those of β-BBO. However, the nonlinear optical properties of α-BBO crystal are nonexistent due to the centric symmetry with its crystal structure. α-BBO crystal is not recommended for NLO processes.
Advantages
•High UV transmittance；
•Large birefringence；
•High damage threshold；
•Stable physical and mechanical properties.
Basic Properties of α-BBO
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Transparency Range
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190-3500nm
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Density
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3.85g/cm3
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Hygroscopic Susceptibility
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Low
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Hardness (Mohs)
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4.5 |
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Thermal Expansion Coefficients (/℃ )
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-9.3×10-6（C）
-9.5×10-6（A）
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Damage Threshold
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1GW
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Refractive Indices
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no=1.6776，ne=1.5534，at 532nm
no=1.6579，ne=1.5379，at 1064nm
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Sellmeier Equation (λin μm)
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no2=2.7471+0.01878/λ2
-0.01822)-0.01354λ2
ne2=2.37153+0.01224/(λ2-0.01667)-0.01516λ2
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