Laser 2000 provides a range of
different crystal materials for various operations. Crystals can be provided in
boule, wafer, or machined to specific dimensions. They can be supplied coated
or uncoated for a range of different laser types.
Photorefractive Crystals
BaTiO3 / SBN / BSO
Fe:LiNbO3 / Fe: KnbO3
- 4 Wave mixing
- Phase conjugation
- Optical memory and computing
The photorefractive effect is a phenomenon whereby the local
index of refraction is modified by spatial variations of the light intensity.
It is strongly observed when coherent rays interfere with each other in a photorefractive
material which forms a spatially varying pattern of illumination. As a result,
charge carriers are produced in the material which migrate owing to drift or
diffusion and space charge separation effects. The resulting electric field
that is produced induces a refractive index change via the Electro-optic effect.
BaTiO3 (Barium Titanate)
Owing to the large Electro-optic effect present in BaTiO3, two wave mixing amplification
factor can be as high as 4000. Optical phase conjugation can be achieved with
low power CW lasers.
SBN
SBN has a large Electro-optic coefficient delivering a fast response time and high two wavelength mixing gain.
BSO
BSO is the fastest photorefractive crystal to date. The coupling gain can be
enhanced with BSO by application of an external electric field. The cubic crystalline
structure is well suited to polarisation manipulation in 2 and 4 wave mixing configurations.
Fe:LiNbO3
Fe:LiNbO3 is a photorefractive crystal with a large
Electro-optic coefficient, very slow fanning and slow decay.
Fe: KnbO3
Fe: KnbO3 is a photorefractive crystal with a fast response time and high coupling
coefficient. It has the best photorefractive figure of merit for many applications.
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