The equipment of the LLPS laboratory includes equipment that allows conducting tests using the DP LIBS (Double Pulse Laser Induced Spectroscopy) method. The LIBS experimental system is set up on an optical table to eliminate vibrations. It includes pulse nanosecond lasers used to excite the plasma being the object of observation of spectrometers which are main measuring instruments in LIBS. The section (anchor) brings forth our most important laser. We also have a high power fiber laser that can be used to clean surfaces (it was originally purchased as part of the EFDA project to remove fuel and co-deposit from the inner wall of a tokamak).
The spectrometers in the LLPS laboratory allow measurements to be carried out in the entire optical spectrum and partly in UV and IR. We have a spectrometer equipped with an Echelle grid and an image intensifier for sophisticated plasma dynamics research, as well as a compact spectrometer for application experiments.
Many of the experiments are carried out in a vacuum chamber, which allows a pressure of 2-3 * 10 ^ -6 mbarr. An x-y motion table is installed in the chamber enabling remote control of the object mounted on it in the range of 0-50 mm in both directions with a resolution of 1 mm. The chamber is equipped with windows enabling the introduction of the beam and observation of the plasma, one of them is made of glass that allows observation by means of a pyrometer, which is also included in the equipment. Corpuscular time-of-flight diagnostics are attached to the other ports of the chamber: ion collectors and semiconductor detectors that measure electrical signals from ions, as well as x-ray sensors and a charge probe. The signals from all these sensors are recorded with a digital oscilloscope. They are a source of very interesting information about the dynamics of laser plasma.
On the other hand, information on the effects of impulses interacting with the surface is provided by an analysis using a profilomenter and microscopes. The NANOVEA profilometer allows depth analysis with sub-micrometer precision, with a resolution in the x-y axes of 2 um.
LASER LOTIS TII
The LOTIS TII LS-2134D laser is used as the laser pulse source. It delivers pulses with a duration (FWHM) of 12-15 ns, energy up to 200 mJ and repetition frequency up to 10 Hz. The interval between pulses can be set in the range of 0-80 us with a resolution of 1 ns.
The laser can be used to fire other devices through the TTL signal with a rising edge that appears when the flash or q-switch of the first or second channel is turned on (depending on the output used). It is also possible to trigger both the lamp and both q-switches from an external device, e.g. a spectrometer or control system.
Detailed information is available on the manufacturer's website: https://www.lotis-tii.com/eng/productid16.php
MECHELLE 5000 SPEKTROMETER
The MECHELLE 5000 spectrometer used in IFPiLM is equipped with an ISTAR image intensifier. It allows observation of the spectrum in the range from 200 to 900 nm with a resolution of 5000 of 5000 using a 50 um input gap. This means that when measuring 250 nm, the resolution is 50 pm, while 650, 130 pm. By equipping the spectrometer with an image amplifier, you can observe phenomena occurring with the emission of a low signal level, as well as obtain very good time resolution of measurements. Synchronization is very precise thanks to the device equipped with DDG (Digital Delay Generator). It allows adjustment of both delay time and gate opening with nanosecond resolution. This is especially important when studying phenomena occurring in a vacuum, because then the plasma life time is in the order of several hundred nanoseconds (usually not more than 300 ns).
The spectrometer is controlled by the SOLIS software, which allows not only to identify lines in the measured spectrum, but also various types of work, such as the kynetic series, allowing subsequent measurements with constant or variable shift of the observation window, accumulation mode or narrowing of the observed spectral area (so you can get a higher repetition rate).
The data obtained from the spectrometer are processed and analyzed by means of Python programs created by the team, thanks to which batch conversion and intensity calibration are possible, followed by line matching and determination of temperature and electron concentration.
More detailed information about the spectrometer can be found on the manufacturer's website: https://andor.oxinst.com/products/mechelle-spectrograph/mechelle-5000