About PPLN Crystal
About PPLN Crystal
Blog Article
Borates like LBO and BBO also operate properly in broadly tunable optical parametric oscillators and optical parametric chirped-pulse amplification.
If a centered Gaussian beam is used, having SHG of the CW laser for example, the frequency conversion efficiency might be deduced into a normalized efficiency like a operate of wavelength. You should Check out "SHG normalized effectiveness and pump wavelength dependence" for total information and facts.
Undoped PPLN is often operated at temperatures involving one hundred°C and 200°C, to minimize the photorefractive impact that will injury the crystal and bring about the output beam to become distorted.
PPLN contains a substantial index of refraction that leads to a ~fourteen% Fresnel reduction per uncoated area. To raise transmission by way of our crystals, the crystal input and output aspects are AR coated, Hence lowering the reflections at Each and every area to below 1%.
Nonetheless, these a method cannot enable productive use of material's complete transparency wavelength ranges at optimized conversion effectiveness. Moreover, BPM nonlinear wave mixing method takes place during the existence of equally everyday and amazing polarized radiations. When propagating together non-optical axis path of a nonlinear optical crystal, the incredible wave suffers from birefringence wander-off; Whilst common ray will not likely.
A common approach for getting ultrathin crystals would be to very first optically Call a thicker nonlinear crystal with some substrate (e.g. of fused silica) then to polish the crystal all the way down to the essential thickness of e.
Even so, in certain product which include KTP, a grey line is noticed when the crystal is irradiated by noticeable or UV light-weight. The induced absorption is attributed to polarons, where by carriers may in that case be captured e.g. by Ti4+ ions or by Fe3+ impurities within the KTP. Grey monitoring is generally reversible and disappears inside a handful of hrs soon after irradiation. Its energy relies on the crystal quality and so PPLN Crystal to the fabrication process, as well as some vital parameters including the pulse period and pulse repetition amount.
With QPM, all over styles can quite possibly be recognized for selected QPM supplies, as one can engineer the phase-matching condition among mixing waves:
: The QPM framework of PPLN allows for wide tunability in the produced or transformed wavelengths. By adjusting the temperature from the crystal, the period-matching affliction can be tailored, resulting in tunable output throughout a wide range of wavelengths.
Though QPM bulk unit features advantages of larger electric power and bigger aperture purposes, QPM waveguide (WG) can be used to further boost nonlinear wave mixing performance by tightly confining the laser depth around long propagation distance, as shown in determine four.
5 mm to minimize team velocity mismatch and are ideal for frequency doubling or tripling of Ti:sapphire and Yb:doped laser pulses. The critical and noncritical period matching LBO crystals are ideal for next or third harmonic technology of Nd:YAG and Yb:doped lasers.
g. from two-photon absorption. The outcome may be considerably decreased by doping the fabric with magnesium oxide (MgO) and/or by using stoichiometric content, which contains fewer with the intrinsic niobium antisite defects. At the same time, equally procedures may reduce the tendency for photorefractive beam distortions resulting from the rise of ionic conductivity.
GWU-Lasertechnik offers all common nonlinear crystals like LBO, BBO and KTP having a wide number of specifications. Beside the well-established products, revolutionary crystals like CLBO or BiBO with excellent Houses for e. g. deep-UV technology or large-electrical power ultrashort pulse lasers can be obtained. No matter if personal items for R & D needs are essential or Charge-successful quantities in smaller, medium or significant batches with in-time supply with the output line are desired: GWU’s focused services helps to locate the most effective Main parts on your application.
An alternative system to attain stage matching ailment between mixing waves is Quasi-Period-Matching (QPM). Quasi-Phase-Matching (QPM) is a method for engineering stage matching condition in nonlinear wave mixing procedure. In the QPM nonlinear wave mixing method, the phase mismatching is compensated by shifting the section relative to every A different amongst mixing waves more than a coherent length via inverting the indication on the nonlinear coefficient in nonlinear medium (including “poling�?to invert the crystal orientation for fabrication of Periodically Poled Lithium Niobate (PPLN)).