BBO Crystal Fundamentals Explained
BBO Crystal Fundamentals Explained
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This efficiency is important, specially when one particular considers the technology from the 266nm wavelength, exactly where even minor inefficiencies can result in considerable Electricity losses.
When choosing an SHG crystal, the heartbeat period in the laser supply have to be taken into consideration. A mismatch in between the length and crystal thickness will cause SHG pulses more time in time and narrower in spectral content material than feasible under excellent disorders.
Last of all, the extensive-angle tunability of BBOs facilitates customization like never prior to. According to the certain necessities of the application, the crystal might be modified with precision, guaranteeing that the output is always optimized.
In an effort to use the desired CW injury threshold of the optic, it's important to understand the next:
BBO incorporates a low susceptibility to moisture. The AR coating or even the protecting coating (P-coating) around the crystal faces can guard the faces from moisture to some extent. It is okay to depart the crystal inside the setup for most optics labs with RH =< forty%. On the other hand, we recommend to shop the crystal in a desiccator if it won't be utilized for over > 2 weeks to extend the crystal life time.
They exhibit superior homogeneity about massive volumes and possess a substantial injury threshold, but are hygroscopic and also have a small nonlinearity.
The cutting angle relies upon upon the preferred phase-matching challenge for frequency conversion apps. Stage matching describes matching the section speeds of varied beams related to nonlinear processes so that they Establish up constructively over fars away In the crystal.
g. twenty μm. The group velocity mismatch from the thicker substrate product may well not make any difference, because the nonlinear interaction can take location only in the thin crystal. The substrate only serves to mechanically stabilize The BBO Crystal skinny nonlinear crystal.
The group velocities of the elemental and next harmonic pulses are diverse, even though section-matched, along with the magnitude from the team velocity mismatch depends upon the crystal Qualities as well as the optical frequencies while in the pulses.
The Strength density of one's beam really should be calculated with regards to J/cm2. The graph to the right shows why expressing the LIDT being an Strength density gives the ideal metric for brief pulse sources. Within this regime, the LIDT offered as an Strength density may be applied to any beam diameter; 1 isn't going to have to compute an altered LIDT to adjust for alterations in spot sizing.
Extreme optical intensities for the duration of Procedure could instantaneously problems a crystal. Regretably, nonlinear crystals normally need to be operated not far from their optical injury threshold to achieve a adequately superior conversion performance. This suggests a trade-off involving conversion effectiveness and crystal lifetime.
Though the exam effects are only agent of 1 coating operate, Thorlabs specifies problems threshold values that account for coating variances.
3rd harmonic era (THG): We use THG to evaluate our parts�?nonlinear conversion success and section-matching angle for just a specified enter wavelength. We Guantee that our products and solutions satisfy the specs for THG programs.
Huge angular wander-off BBO crystals have a big angular wander-off that triggers spatial splitting between numerous polarization parts of sunshine when circulating with a BBO crystal.