Neodymium-doped yttrium orthovanadate
Neodymium-doped yttrium orthovanadate (Nd:YVO4) is a crystalline material formed by adding neodymium ions to yttrium orthovanadate. It is commonly used as an active laser medium for diode-pumped solid-state lasers. It comes as a transparent blue-tinted material. It is birefringent, therefore rods made of it are usually rectangular.
As in all neodymium-doped laser crystals, the lasing action of Nd:YVO4 is due to its content of neodymium ions, which may be excited by visible or infrared light, and undergo an electronic transition resulting in emission of coherent infrared light at a lower frequency, usually at 1064 nm (other transitions in Nd are available, and can be selected for by external optics).
Basic properties
- Atomic density: ~1.37×1020 atoms/cm3
- Crystal structure:
- zircon tetragonal (tetragonal bipyramidal)
- space group D4h
- a=b=7.12, c=6.29
- Mohs hardness: Glass-like, ~5
- Thermal expansion coefficient:
- αa=4.43×10−6/K
- αc=11.37×10−6/K
- Thermal conductivity:
- parallel to C-axis: 5.23 W·m−1·K−1
- perpendicular to C-axis: 5.10 W·m−1·K−1
Optical properties
- Lasing wavelengths : 914 nm, 1064 nm, 1342 nm
- Crystal class : positive uniaxial, no=na=nb, ne=nc,
- no=1.9573, ne=2.1652, at 1064 nm
- no=1.9721, ne=2.1858, at 808 nm
- no=2.0210, ne=2.2560, at 532 nm
- Fluorescence lifetime (spontaneous emission lifetime) as a function of Nd ions concentration:
Nd concentration (atom %) | Fluorescence lifetime (μs)@ 1064 nm | Reference |
0.4 | 110 | J. Appl. Phys. 49, 5517-5522 (1978). |
1.0 | 100 | Castech web site |
1.1 | 90 | Casix web site |
2.0 | 50 | Casix web site |
- Absorption cross-section at 808 nm : 5.5×10−20 cm²
- Emission cross-section at 1064 nm : 38×10−19 cm² (Reference: JOSA 66, 1405-1414 (1976).)
- Polarized laser emission : π-polarization; parallel to optic axis (c-axis) (for a-cut crystal)
- Gain bandwidth : 0.96 nm (257 GHz) at 1064 nm (for 1.1 atm% Nd doped)
- Absorption coefficients at 808 nm for different doping conenctrations:
See also
- Yttrium aluminium garnet (YAG)
References
- H. E. Rast, H. H. Caspers, and S. A. Miller (1968). "Infrared Spectral Emittance and Optical Properties of Yttrium Vanadate" (abstract). Phys. Rev. 169 (3): 705–709. Bibcode:1968PhRv..169..705R. doi:10.1103/PhysRev.169.705.
- O. Guillot-Noel, B. Bellamy, B. Viana, D. Gourier (1999). "Correlation between rare-earth oscillator strengths and rare-earth–valence-band interactions in neodymium-doped YMO4 (M=V, P, As), Y3Al5O12, and LiYF4 matrices" (abstract). Phys. Rev. B 60 (3): 1668–1677. Bibcode:1999PhRvB..60.1668G. doi:10.1103/PhysRevB.60.1668.
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