Homepage MolTech
Print this frame


Passive q-switching has become widely used technique in solid state lasers development. The application of saturable absorbers simplifies considerably laser design, makes it more compact and cheap. The saturable absorbers became successfully applied in diode pumped microchip lasers.
top Cr+4:YAG passive Q-switch To Request Form
Cr+4:Y3Al5O12 or Cr+4:YAG - is a material that can be used as an active media for CW, pulsed or self mode-locked tunable NIR solid-state lasers with tunability range 1340 - 1580 nm as well as a media for Q-switching in lasers with operating wavelength at 950 - 1100 nm. It is particularly useful in practical applications because of convenient absorption band of Cr+4around 1 mm which gives possibilities to pump it by regular Nd:YAG lasers. A saturation of absorption in the band at 1060 nm is useful for application in small sized Nd:YAG oscillators with flash lamp or laser diode pumping instead of based on dye or LiF:F-center passive Q-switches. Using the Cr+4:YAG crystal the self mode-locking (KML) regime is achievable. It gives an opportunity to build the laser source with pulse duration shorter then 100 fs at 1450 - 1580 nm.
Finally, its high thermal and radiation stability as well as excellent optical and mechanical properties will give you an opportunity to design reliable devices based on the crystal.

Technical Specifications:

Wavelength, nm 950 - 1100 nm
Initial transmittance, % 15 - 90
Initial absorption coefficient, cm-1 0.05 - 3.00
Aperture, mm 5 - 12
Contrast > 8 - 10
Optical length, mm 1 - 40
Damage threshold, J/cm2 > 4
Long-term stability > 15 years

top GSGG : Cr4+ passive Q-switch To Request Form
Gadolinium-scandium-gallium garnet doped with chromium and magnesium GSGG:Mg:Cr4+ is a material for passive Q-switching in 1 µm region. The valence state of chromium ion Cr4+ is provided by use of charge compensator. The crystals are grown by Zchochralski method in argon-oxigen atmosphere. Crystals of GSSS:Mg:Cr possessing the contrast parameter close to the one of YAG:Cr4+ have some advantages such as: possibility to provide necessary initial transmission at less thickness (typical thickness is about 1mm), transparency in the visible range which simplifies the alignment procedure.
Initial transmission 5 - 95 %
Absorption index at the wavelength of 1.067 µm 0.2-10 cm-1
Contrast 6 - 7
Thickness 0.5 - 5 mm
Diameter 6 - 9 mm
Relaxation time of the exited state (4A24T1(4F) absorption) 200 ns

Application: for short-pulse lasers of IR spectral range

R.Buzelis, A.Dementiev, E.Kosenko, E.Murauskas, F.Ivanauskas, M.Radziunas "Determination of absorption cross sections of Cr4+:GSGG and Cr4+:YAG passive Q-switches at the generation wavelength of Nd:YAG laser", Lithuanian Journal of Physics, 37(4), pp 291-298, 1997

top YAG:V3+ passive Q-switch To Request Form
The crystals of Yttrium-Aluminum Garnet doped with three-valence vanadium V3+ in tetrahedral position suggest efficient q-switching for lasers operating in 1.3 µm region. The absorption band between 1.0 - 1.5 µm is attributed to 3A23T2 transition of V3+ ion in tetrahedral position of garnet lattice. The crystals are grown by oriented crystallization method. Concentration of V3+ in tetrahedral position is controlled by growth and annealing conditions.The efficient q-switching of lasers operating at 1.3 micron has been obtained with a number of active mediums such as YAG:Nd, YVO4:Nd, KGd(WO4)2:Nd under flash-lamp and laser diode pumping.
Initial transmission 5 - 95 %
Contrast 5 - 6
Thickness 0.5 - 5 mm
Diameter 5 - 7 mm
Ground-state absorption cross-section at 1.32 µm 7.3 x 10-18 cm2
Ground-state absorption cross-section at 1.06 µm 3.0 x 10-18 cm2
Relaxation time of the exited state (3T23A2 absorption) 20 ns

Application: for short-pulse lasers of IR spectral range 1.06 - 1.4 µm

A.M.Malyarevich, I.A.Denisov, K.V.Yamashev, V.P.Mikhailov, R.S.Conroy, B.D.Sinclair, "V:YAG - a new passive Q-switch for diode pumped solid state lasers", Appl. Phys. B 67 (1998), p. 555

top Co+2:MgAl2O4 passive Q-switch To Request Form
Spinel crystal is a material having high optical damage threshold and low optical losses in 1.3 - 1.6 µm spectral range. Co2+-activated MgAl2O4 (Co:MALO, Co:spinel) can be used as a media for passive Q-switch of lasers which operate in the spectral range of 1.3 - 1.6 µm, for example 1.32 µm and 1.44 µm Nd:YAG lasers, 1.31 µm iodine lasers and especially 1.54 µm erbium glass lasers.
High enough absorption cross-section of Co+2 ions together with practical absence of excited state absorption makes this material a very efficient passive Q-switcher (that does not require intracavity focusing) for various types of erbium glass lasers, including diode-pumped microchips.

Technical Specifications:

Absorption band, µm 1.3 - 1.6
Operating transition 4A2 -4T1 (4F)
Absorption cross-section at 1.54 µm, cm2 2 x 10-19
Bleached state lifetime at 300K, ns 200
Dopant level, cm-3 2 x 10-17- 3 x 1019
Initial transmission, % 10 - 99
Initial absorption coefficient at 1.54 µm, cm-1 0.06 - 10
Aperture, mm 5 - 12
Plate thickness, mm 0.2 - 5

Co+2:MgAl2O4 passive Q-switch Cat.-No.: D-120-01

top To Request Form
 Quality -> UP
No more loosing of energy !   Up to 50% saved !
Costs -> DOWN 

Why piShaper saves laser energy ? ::more details ...

piShaper - laser beam shaping never was so easy !

With this unique tool it is possible to convert a Gaussian laser beam into a collimated flat-top (or top-hat) beam with nearly 100% efficiency. piShaper produces a collimated flat-top beam over a large working distance. This enables the beam to be easily manipulated and re-sized with conventional imaging optics.

Almost the same effective sizes of input and output beams (approx. 6 mm) make it easy to integrate piShaper to your application.

Being originally designed as achromatic for two laser wavelength, 1064 nm (Nd:YAG) and 632.8 nm (He-Ne), piShaper could be easily tuned to work at other laser wavelengths within the range 355 1200 nm.
Technical Specifications:
Type piShaper 6_6
Input beam Gaussian, diameter 6 mm (1/e2)
Output beam - Flat-top, uniformity within 5%
- Diameter 6 mm
- High edge steepness
Transmission >95% within 800-1100 nm range
Wavelength range 355 - 1200 nm
Design wavelengths   1064 nm (Nd:YAG) , 632.8 nm (He-Ne)
Other features

- Achromatic for design wavelengths
- Compact design
- Custom design on request
  (other wavelength ranges, beam diameters, input and output beams shapes)
- Long working distance

Overall dimensions - Diameter 24 mm, length 78 mm
Weight < 80 g
Mounting M18x0.5
laser beam shaper

Ideal for applications in:

  • Holography
  • Information processing
  • Printing
  • Marking
  • Scribing
  • Illumination
laser beam shaper
  • Material micromachining
  • Laser ablation
  • Laser annealing
  • Welding of metals and plastics
  • Soldering
  • Cutting