The calculation previously mentioned assumes a uniform beam depth profile. It's essential to now consider hotspots during the beam or other non-uniform intensity profiles and roughly determine a utmost electricity density.
A1: Sure, BBO crystals have a substantial harm threshold, building them appropriate for higher-power laser units. Their potential to withstand significant laser intensities with out struggling from optical injury would make them an outstanding choice for frequency conversion in large-ability lasers.
There's two velocities that define the propagation of sunshine in optical media: the section and team velocities. The period velocity may be the speed from the provider, the oscillation of the electrical discipline, and also the velocity that is certainly matched amongst the basic and next harmonic frequencies for stage matching. The section velocity relative for the velocity of light within a vacuum is defined with the index of refraction.
Nonetheless, it’s vital that you Notice that though BBO crystals can handle higher power, they need to continue to be made use of within just their specified ability array to avoid likely destruction and assure optimal performance.
Other period matching situations can also be probable. Critical Variety-II phase matching utilizes an oe-o or eo-e for favourable and adverse uniaxial crystals. Non-essential period matching makes use of crystal temperature to attain phase matching as opposed to angular tuning.
The performance with the SHG procedure decreases considerably as the basic beam diverges from its target, since the pulse Vitality is dispersed throughout a bigger beam cross segment.
Determine fourteen displays a departure from a perfect polarization orientation for Form-I SHG, exactly where the incident fundamental area contains a linear polarization but is rotated by a diploma γ within the principal standard axis .
As illustrated in the next desk, the shorter the crystal, the broader the reference pulse spectrum. The desk down below assumes a elementary Middle wavelength while in the around-IR.
When pulse lengths are among one ns and one µs, laser-induced hurt can happen both due to absorption or perhaps a dielectric breakdown (thus, a consumer will have to check equally CW and pulsed LIDT). Absorption is either as a consequence of an intrinsic residence of your optic or as a result of surface irregularities; As a result LIDT values are only legitimate for optics Assembly or exceeding the surface excellent specifications specified by a company.
The section velocity is the speed at which the sphere copyright, i.e. the sine wave, travels in a material. The rate at which a pulse envelope travels in a material is called the team velocity and defines the pace of your Power packet comprising the optical pulse traveling by the fabric.
This calculation assumes a uniform beam more info intensity profile. You must now regulate this Vitality density to account for hotspots or other nonuniform depth profiles and around work out a highest Electrical power density. For reference a Gaussian beam typically features a most Electricity density that is definitely twice that of the 1/e2 beam.
Up coming, the power/Vitality is either amplified or reduced plus the optic is uncovered at 10 new locations. This method is repeated until eventually injury is observed. The damage threshold is then assigned being the very best ability/Electrical power that the optic can endure without having triggering destruction. A histogram for instance that underneath signifies the testing of one BB1-E02 mirror.
However, the nonlinear optical Homes of a-BBO crystal is vanished because of the centric symmetry with its crystal construction. It's not necessarily advised to use for NLO processes.
In frequency conversion, BBO crystals are utilized to change the shade of laser mild, enabling the manufacture of an array of colors that are not straight obtainable from out there laser sources. In electro-optic modulation, They are really applied to manage the intensity, period, polarization, or course of the laser beam.