Potassium Titanyle Arsenate
KTA
Potassium Titanyle Arsenate crystals (KTA) crystals feature large non-linear optical and electro-optical coefficients in comparison to KTP and have the added benefit of significantly reduced absorption in the 2.0µm- 5.0µm region. The large non-linear coefficients are combined with broad angular and temperature bandwidths. Additional advantages of the Arsenates are low dielectric constants, low loss tangent and ionic conductivities orders of magnitude less than KTP. Single crystals of these Arsenates are chemically and thermally stable, non-hygroscopic and are highly resistant to high intensity laser radiation.
KTA is used for second harmonic generation (SHG), sum and difference frequency generation (SFG)/(DFG), optical parametric oscillation (OPO), electro-optical Q-switching and modulator and as substrates for optical waveguides. OPO devices based on these crystals are reliable solid-state sources of tunable laser radiation exhibiting energy conversion efficiencies above 50%.
KTA has a very high damage threshold. No optical damage was observed at levels 10GW/cm2 – 20GW/cm2 with picosecond dye lasers. This crystal is grown using high temperature flux technique.
Optical and spectral properties | |
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Transmission range | 350 ‐ 5500
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Refractive index @ 1064 nm | nx = 1,782 ny = 1,790 nz = 1,868
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Average refractive index | 1,8 |
NLO coefficients in pm/V | d15 = 2,3 d24 = 3,2 d31 = 2,8 d32 = 4,2 d33 = 16,2 |
Absorption loss in %/cm @532 nm and @1355 nm | <0,05
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Absorption loss in %/cm @ 3475 nm | <5
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Phase matching range in nm | 1075 ‐ 1134 |
Wavelength in nm: | Pumpe ⇒ 1064 Signal ⇒ 1533 Idler ⇒ 3475 |
Damage threshold in MW/cm2 (1064 nm, 10 ns, 10 Hz) | 600
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Electro-optical constants (low frequency) in pm/V | r33 = 37,5 r23 = 15,4 r13 = 11,5
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Physical properties | |
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Chemical formula | KTiOAsO4 |
Density in g/cm3 | 3,454
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Melting point in °C | 1130 |
Lattice constants in Å | a= 13,125 b = 6,5716 c = 10,786 |
Crystal structure | orthorhombic
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Hygroscopic susceptibility | no
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Thermal conductivity in W/(m·K) | k1 = 18 k2 = 19 k3 = 21 |
Mohs hardness | 3
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Spectral properties | |
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sample thickness: 10 mm |