- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Analysis of alloy and solar cells with double-pulse calibration-free laser-induced breakdown spectroscopy
摘要： We applied variant of calibration free laser induced Breakdown Spectroscopy (CF-LIBS) approach for the compositional analysis of standard Gd/Ge/Si alloy and solar cells. The double pulse laser induced plasma was produced on the sample surface and the emission spectra were recorded at optimized interpulse delay and energy ratio. The Plasma temperature, determined using Boltzmann plot, was used to determine the concentration of all species present in a sample. The results are compared with reference values as well as conventional CF-LIBS results, which show that conventional and variant CF-LIBS results are similar and in close agreement to reference values. It is worth mention that the variant CF-LIBS results, but the approach is simpler and faster. Therefore, this approach was applied to three unknown polycrystalline silicon solar cells, which yield Al, C, Ca, Fe, In, Ti, Sb and Sn in the parts per million (ppm). This approach can potentially be applied for real-time trace monitoring in manufacturing processes of photovoltaic devices where conversion e?ciency depends strongly on impurities’ concentration.
关键词： Alloy and solar cells,Double pulse LIBS,Laser induced plasmas,Quantitative elemental analysis,Calibration free LIBS,Plasma parameters
更新于2025-09-23 15:21:01
-
Interaction of two counterpropagating laser induced plasmas and shock waves in air
摘要： The interaction of two counterpropagating plasmas and shockwaves due to a 7 ns laser induced breakdown (LIB) of ambient atmospheric air was studied using the 2D emission and shadowgraphic imaging technique. The effect of separation distance (d) between the two plasma sources and their energy ratio on plasma and shockwave evolution is presented. These low density and low temperature plasma sources form a stagnation layer in the interaction zone that showed an interesting dependence on the input energy of the sources. The interaction dynamics of the two counterpropagating plasma plumes and the shock waves in ambient air are compared with that of the respective single plasma source to explicitly bring out the energy exchange during the interaction. The evolution of a plasma jetlet, studied by 2D emission images and shadowgraphic imaging, has shown very good correlation giving valuable insight into the role of a plasma induced shockwave on the expanding plasma. The propagation of the shock front of the high energy source through the plasma of a low energy source is observed to predominantly lead to the formation of a jetlet and its evolution.
关键词： laser induced plasmas,plasma jetlet,plasma interaction,shock waves,counterpropagating,stagnation layer
更新于2025-09-23 15:19:57
-
Complementary Characterization of Laser-Induced Plasmas by Optical Emission Spectroscopy and Triple Langmuir Probe
摘要： In this article, we study the temporal evolution of the electron density and temperature of carbon laser-produced plasmas (LPP) using a combination of optical emission spectroscopy (OES) and the triple Langmuir probe (TLP) method. OES has been widely used to characterize LPPs but it is limited to distances relatively close to the target. On the other hand, the main advantage of TLP over the single-probe method is that it allows to obtain simultaneous measurements of electron temperature (Te) and density (Ne), without any voltage sweeping. In this article, we compare both techniques; measurements by OES were performed at distances from the target <1 cm, whereas the triple probe was employed for distances >5 cm. The plasma was generated by focusing nanosecond laser pulses onto a high purity graphite target placed inside a vacuum chamber. Our results show that the values of Te measured using both techniques predict decreasing exponential behavior. Ne determined by the spectral line Stark broadening in OES (<1 cm) was two orders of magnitude larger than that measured by the TLP (>5 cm). This difference in the electron density can be explained by radiative recombination and the presence of different kinds of plasma species detected by the TLP technique. The results show that both methods are complementary and their combination can be used to characterize LPP in a wide range of distances and timescales.
关键词： triple Langmuir probe (TLP),optical emission spectroscopy (OES),Laser-induced plasmas
更新于2025-09-11 14:15:04