Deuterated potassium dihydrogen phosphate (KDPO or KHPO) or DKDP
single crystal
In materials science, a single crystal (or single-crystal solid or monocrystalline solid) is a material in which the crystal lattice of the entire sample is continuous and unbroken to the edges of the sample, with no Grain boundary, grain bound ...
s are widely used in
non-linear optics
In mathematics and science, a nonlinear system (or a non-linear system) is a system in which the change of the output is not proportional to the change of the input. Nonlinear problems are of interest to engineers, biologists, physicists, mathem ...
as the second, third and fourth harmonic generators for
Nd:YAG and
Nd:YLF lasers. They are also found in
electro-optical
Electro–optics is a branch of electrical engineering, electronic engineering, materials science, and material physics involving components, electronic devices such as lasers, laser diodes, LEDs, waveguides, etc. which operate by the propaga ...
applications as
Q-switches for
Nd:YAG,
Nd:YLF,
alexandrite
The mineral or gemstone chrysoberyl is an aluminate of beryllium with the formula Be Al2 O4. The name chrysoberyl is derived from the Greek words χρυσός ''chrysos'' and βήρυλλος ''beryllos'', meaning "a gold-white spar". Despite ...
and
Ti-sapphire laser
A titanium-sapphire laser (also known as a Ti:sapphire laser, Ti:Al2O3 laser or Ti:sapph) is a tunable laser which emits red and near-infrared light in the range from 650 to 1100 nanometers. This type of laser is mainly used in scientific research ...
s, as well as for
Pockels cells.
Encyclopedia of Laser Physics and Technology
DKDP is monopotassium phosphate
Monopotassium phosphate (MKP) (also, potassium dihydrogen phosphate, KDP, or monobasic potassium phosphate) is the inorganic compound with the formula KH2PO4. Together with dipotassium phosphate (K2HPO4.(H2O)x) it is often used as a fertilizer, ...
(KDP, or KHPO), but using deuterium. Replacement of hydrogen by deuterium
Deuterium (hydrogen-2, symbol H or D, also known as heavy hydrogen) is one of two stable isotopes of hydrogen; the other is protium, or hydrogen-1, H. The deuterium nucleus (deuteron) contains one proton and one neutron, whereas the far more c ...
in DKDP lowers the frequency of O–H vibrations and their overtones
An overtone is any resonant frequency above the fundamental frequency of a sound. (An overtone may or may not be a harmonic) In other words, overtones are all pitches higher than the lowest pitch within an individual sound; the fundamental i ...
(high-order harmonics). Absorption of light by those overtones is detrimental for the infrared lasers, which DKDP and KDP crystals are used for. Consequently, despite higher cost, DKDP is more popular than KDP.
DKDP crystals are grown by a water-solution method at usual level of deuteration >98%.
See also
*Beta barium borate
Barium borate is an inorganic compound, a borate of barium with a chemical formula BaB2O4 or Ba(BO2)2. It is available as a hydrate or dehydrated form, as white powder or colorless crystals. The crystals exist in the high-temperature α phase and ...
(BBO) – another popular non-linear crystal
*Lithium triborate
Lithium triborate (LiB3O5) or LBO is a non-linear optical crystal. It has a wide transparency range, moderately high nonlinear coupling, high damage threshold and desirable chemical and mechanical properties. This crystal is often used for sec ...
(LBO) – another popular non-linear crystal
*Monopotassium phosphate
Monopotassium phosphate (MKP) (also, potassium dihydrogen phosphate, KDP, or monobasic potassium phosphate) is the inorganic compound with the formula KH2PO4. Together with dipotassium phosphate (K2HPO4.(H2O)x) it is often used as a fertilizer, ...
(KDP) – another popular non-linear crystal
*Non-linear optics
In mathematics and science, a nonlinear system (or a non-linear system) is a system in which the change of the output is not proportional to the change of the input. Nonlinear problems are of interest to engineers, biologists, physicists, mathem ...
*Potassium titanyl phosphate
Potassium titanyl phosphate (KTP) is an inorganic compound with the formula . It is a white solid. KTP is an important nonlinear optics, nonlinear optical material that is commonly used for second-harmonic generation, frequency-doubling diode-pum ...
(KTP) – another popular non-linear crystal
*Second-harmonic generation
Second-harmonic generation (SHG), also known as frequency doubling, is the lowest-order wave-wave nonlinear interaction that occurs in various systems, including optical, radio, atmospheric, and magnetohydrodynamic systems. As a prototype behav ...
(SHG)
* Third-harmonic generation (THG)
*Two-photon absorption
In atomic physics, two-photon absorption (TPA or 2PA), also called two-photon excitation or non-linear absorption, is the (almost) simultaneous Absorption (electromagnetic radiation), absorption of two photons of identical or different frequencie ...
(TPA)
* Organic nonlinear optical materials
References
{{reflist
Nonlinear optical materials
Phosphates
Potassium compounds
Deuterated compounds