Lithium Triborate is a nonlinear optical crystal discovered and developed by Fujian Institute of Research on the Structure of Matter, Chinese Academy of Science. It has a wide transparency range, high damage threshold, a relatively large effective SHG coefficient, and desirable chemical and mechanical properties. These properties make it suitable for frequency mixing and other nonlinear optical applications.
Features:
- Wide transmission region from 160 nm to 2600 nm
- Wide acceptance angle and small walk-off
- Relatively Large effective second-harmonic-generation (SHG) coefficient
- High damage threshold
- High Optical homogeneity
- Non-critical phase matching (NCPM) in a wide wavelength range
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Figure 1: External transmittance curve of a 10mm lithium triborate sample
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Crystal Structure |
Orthorhombic
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lattice constant (Å) |
a = 8.4473, b = 7.3788, c = 5.1395
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Melting Point (°C) |
834
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Optical Homogeneity (/cm) |
≈10-6
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Mohs Hardness |
6
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Density (g/cm^3) |
2.47
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Absorption Coefficient (/cm) |
α<0.001 at 1064nm
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Coefficient of Thermal Expansion ( /K)
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ax: 10.8X10-5 ay: -8.8X10-5 az: 3.4X10-5 |
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Transmission Range (nm) |
160~2600
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Damage Threshold (GW/cm2)
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18.9 at 1053nm (1.3ns)
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Refractive Indices |
nx = 1.5656, ny = 1.5905, nz=1.6055 at 1064nm nx = 1.5785, ny = 1.6065, nz=1.6212 at 532nm nx = 1.5973, ny = 1.6286, nz=1.6444 at 355nm
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Sellmeier Equations (λ in um)
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nx2 = 2.454140+0.011249/(λ2-0.011350)-0.014591×λ2-6.60×10-5×λ4 ny2 = 2.539070+0.012711/(λ2-0.012523)-0.018540×λ2-2.0×10-4×λ4 nz2 = 2.586179+0.013099/(λ2-0.011893)-0.017968×λ2-2.26×10-4×λ4
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Nonlinear Optical Coefficients (pm/V)
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d31 = 1.05 d32 = -0.98 d33 = 0.05 |
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Table 1: LiB3O5 Properties
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