PPLN Crystals
Periodicaly Poled Lithium Niobate (PPLN) offers high efficiency wavelength conversion in the 460nm to 5100nm range. Our proprietary poling process creates high fidelity PPLN periods from 4.5μm to 33μm+ and is ideal for volume manufacture. Below is a list showing our standard off-the-shelf crystals categorised into the most popular nonlinear parametric processes; Second Harmonic Generation (SHG), Sum Frequency Generation (SFG), Difference Frequency Generation (DFG), and Optical Parametric Oscillation/Generation (OPO/OPG).
Our standard range of PPLN crystals are designed to work with a wide range of common laser wavelengths. Each device includes multiple gratings for flexible temperature and wavelength operation. Our crystals are AR coated and polished to: <λ/4 flatness, parallel to ±5minutes, with better than 20-10 scratch-dig and fewer than two 100μm edge chips per facet. All of our standard products undergo rigorous quality inspection and are supplied clip-mounted and off-the shelf.
Custom crystal lengths, thicknesses, AR coatings, and grating designs are also available on request - visit our Custom PPLN page for more details.
PPLN for Second Harmonic Generation
Our SHG crystals are designed to frequency double a wide range of common laser wavelengths. Each crystal type is available in two lengths; 1mm for short pulsed pump sources and 10mm for longer pulses or continuous wave (cw) pump sources.
Key Features:
- AR coated; input facet <0.5%R @ pump, output facet <0.5%R @ SHG wavelengths
- Multiple gratings; temperature / wavelength flexibility
- High efficiency frequency doubling of wavelengths in the range 980nm to 2200nm
- Crystals supplied mounted in 1mm or 10mm clips
PPLN for Sum Frequency Generation
SFG can be used to generate wavelengths in the visible range by pumping an appropriate PPLN grating with two longer wavelengths. Our SFG crystals are designed to be pumped with a fixed wavelength laser and a tunable laser, allowing the output wavelength to be selected as a direct function of the tunable input wavelength and crystal temperature.
Key Features:
- AR coated; input facet <0.5%R @ pump, output facet <0.5%R @ SFG wavelengths
- Multiple gratings; flexible tuning via temperature, grating or pump wavelength selection
- High efficiency generation of visible wavelengths
- Crystals supplied mounted in 1mm or 10mm clips
PPLN for Difference Frequency Generation
DFG allows wavelengths in the 2-5µm range to be generated by mixing two shorter wavelengths in a suitable PPLN crystal. Our DFG crystals are designed to mix the frequencies of a Nd:YAG laser and a tunable Ti-Sapphire (or similar) lasers. The output wavelength can be tuned with each PPLN grating by adjusting the input laser wavelength and varying the PPLN temperature.
Key Features:
- AR coated; input facet <1%R @ pump, output facet <2% @ DFG wavelengths
- Multiple gratings; flexibile tuning via temperature, grating or pump wavelength selection
- High efficiency generation of 2-5µm
- Crystals supplied mounted in 20mm or 40mm clips
PPLN for Optical Parametric Generation/Oscillation
Our OPO crystals are designed to be pumped using a wide variety of laser sources with wavelengths in the region of 1064nm. These crystals can also be used for other applications such as optical parametric generation and optical parametric amplification.
Key Features:
- AR coated: input and output facets <1%R @ specified pump, signal and idler wavelengths
- Multiple gratings; continuous tuning of signal / idler via temperature and period selection
- High efficiency generation of wavelengths between 1.3 to 5.0μm.
- Crystals supplied mounted in 20mm or 40mm clips
