Frequency Mixing in Periodically Poled Crystals

The MixTrain is using quasi-phase matching in periodically poled crystals for sum- or difference frequency mixing of two cw-lasers. Typically, one of the laser will be a tunable Titanium-Sapphire laser like the Matisse TR while the other laser is a powerful fixed wavelength fibre laser operating at 1.55 μm or 1.06 μm. The system uses a motor controlled translation stage for changing the period of the crystal and a temperature stabilized oven capable of heating up to 200°C. All optics for beam shaping, polarization control, beam combination, and beam separation are included. An optical diode isolates the fibre laser input from back reflections from the setup.

Tuning Ranges


Fibre Laser2) Matisse Range Power1)
1) Matisse 2 W output, fibre laser 12 W output
2) For other lasers contact Sirah
1550 nm 690 .. 1015 nm Sum 480 .. 610 nm 1.0 Watt
Difference 1.3 .. 2.8 μm 35 mWatt
1064 nm 690 .. 1015 nm Sum 420 .. 518 nm 1.0 Watt
Difference 2.0 .. 4.2 μm 35 mWatt
Standard Crystals
3) scan range without change of crystal temperature
PPCGG Green Gap Crystal, 490 nm .. 550 nm 20 GHz scan range3)
11 period domains
PPCIR Infra Red Crystal, 2 μm .. 2.8 μm 60 GHz scan range3)
11 period domains

Periodically Poled Crystal Characteristics

Maximum Length 70 mm
Maximum Width 31 mm
Temperature Range 20 .. 200 °C
Recommended Size of Period Domain 1 mm x 1mm
Beam Polarization vertical


4) please contact Sirah for compatibility with other pump lasers
Pump Lasers 4) Matisse Titanium-Sapphire Laser (5 Watt output)
Single-Frequency Fibre Laser (15 Watt output)
Computer Control Windows XP / Windows Vista / Windows 7

Optical Layout


All Dimensions in mm. Specifications are subject to change without notice.

Literature & Downloads

Datasheet MixTrain