LiTaO3 Crystal
Lithium tantalate (LiTaO3) is a material used in various fields such as electronics and nuclear fusion, due to its properties as a nonlinear optical material, piezoelectric element, and pyroelectric element.
Also known as lithium tantalum oxide, it is a complex oxide composed of lithium oxide (Li2O) and tantalum oxide (Ta2O5) in a 1:1 composition.
This crystal has a trigonal crystal system ilmenite-like structure and is a thermally and chemically stable crystal at about 1,650℃.
Single crystals are used as nonlinear optical materials in laser media and as piezoelectric elements in piezoelectric ceramics and surface acoustic wave elements.
In addition, lithium tantalate crystals are also utilized in nuclear fusion research, and it has been reported that they can achieve nuclear fusion of deuterium samples regardless of extreme temperatures or pressures.
Basic Properties
| Crystal Structure | Trigonal, space group R3c, Point group 3 m |
|---|---|
| Cell Parameters | a = 5.154 Å, c = 13.781 Å |
| Melting Point | 1650℃ |
| Curie Temperature | 607℃ |
| Mohs Hardness | 5.5 |
| Density | 7.46 g/cm3 |
| Dielectric Constant |
ε11/ε0: 51.7 ε33/ε0: 44.5 |
| Elastic Stiffness Coefficient |
CE11: 2.33 (×1011 N/m2) CE33: 2.77 (×1011 N/m2) |
| Piezoelectric Strain Constant |
d22: 2.4 (×10-11 C/N) d33: 0.8 (×10-11 C/N) |
| Transmission Range | 400 - 4500 nm |
| Electro-Optical Coefficients | r33 = 30.4 pm/V |
| Refractive Index at 632.8 nm | no = 2.176, ne = 2.180 |
Typical Specifications
| Type Specifications | Boule | Boule | Wafer | Wafer |
|---|---|---|---|---|
| Diameter | Φ3" | Φ4" | Φ3" | Φ4" |
| Length or Thickness | ≤100 | ≤50 | ≤0.35 - 0.5 | ≤0.35 - 0.5 |
| Orientation | ※ | ※ | ※ | ※ |
| Ref.Flat Orientation | X,Y | X,Y | X,Y | X,Y |
| Ref.Flat Length | 22 ± 2 mm | 32 ± 2 mm | 22 ± 2 mm | 32 ± 2 mm |
| Front Side Polishing | Mirror polished 5-15 Å | Mirror polished 5-15 Å | ||
| Back Side Lapping | 0.3-1.0 μm | 0.3-1.0 μm | ||
| Flatness (µm) | ≤15 | ≤15 | ||
| Bow (µm) | ≤25 | ≤25 |