This information dives deep into the advantages and distinctive Homes of BBO crystal and its paramount importance in economical frequency doubling and harmonics era at 266nm.
Following, the power/Electrical power is possibly elevated or diminished and also the optic is exposed at ten new spots. This method is repeated until injury is noticed. The injury threshold is then assigned to be the best electrical power/Strength the optic can endure with out resulting in hurt. A histogram for example that under represents the screening of one BB1-E02 mirror.
The energy in the two waves propagates in directions based on their Poynting vectors. Snell's regulation will not explain the direction of Electrical power circulation, nonetheless it can be employed to estimate the route in the k-vector in the crystal.
The Z-axis is parallel to your optical axis of your crystal and also is Also known as the terrific axis. The X- and Y-axes are parallel on the optical axis and are termed frequent axes.
The sort-I stage matching system depends on matching the common and remarkable indices of refraction for the fundamental and next-harmonic frequencies, that's obtained as a result of exact orientation on the crystal optic axis and enter propagation vector. A centered laser pulse, or beam, has angular articles, formally named spatial frequencies, to produce the compact focal spot.
They show great homogeneity more than huge volumes and possess a large hurt threshold, but are hygroscopic and also have a lower nonlinearity.
A suggested guideline for concentrating femtosecond laser pulses into a nonlinear crystal is to keep up a Rayleigh variety that is definitely a minimum of various situations more time when compared to the length of your SHG crystal. This minimizes the chance of harmful the crystal, together with lessens the destructive more info consequences of spatial section mismatch and spatial (Poynting vector) walk-off.
the chemical toughness; e.g., some crystal resources are hygroscopic, Some others endure chemical modifications when heated in a vacuum chamber for software of a dielectric coating
BBO crystals are delicate and have to have mindful managing to forestall harm to their surfaces. They need to be handled with clean, lint-totally free gloves to stay away from scratching or contaminating their surfaces. When not in use, BBO crystals ought to be stored within a cool, dry position from direct daylight, as prolonged exposure to heat and lightweight can degrade their optical Qualities.
The stage matching angle could be modified by rotating the crystal throughout the y axis. An adjustment that is usually within a couple levels can possibly improve the overall performance in the crystal while in the setup or match A different essential frequency during the crystal's functioning array.
This assets is especially helpful in applications that contain superior-ability lasers or powerful mild sources, mainly because it makes certain the longevity and reliability with the crystal in these kinds of demanding situations.
As illustrated in the next desk, the shorter the crystal, the wider the reference pulse spectrum. The desk below assumes a fundamental Centre wavelength while in the close to-IR.
In the situation of ultrashort pulses the large group velocity mismatch enforces using a shorter crystal, which involves superior optical intensities for a supplied conversion effectiveness.
The 266nm wavelength provides specific interactions that other wavelengths can’t, making it indispensable for detecting and researching selected compounds.