Enhanced laser-induced breakdown spectroscopy using the combination of fourth-harmonic and fundamental Nd:YAG laser pulses

摘要: Abstract We have studied the combination of fourth-harmonic (266 nm) and fundamental (1064 Nd:YAG laser pulses same irradiance. On a metallic target (Al), sequence ultraviolet (UV) near-infrared (NIR) produces deeper craters can lead under certain conditions to analyte signal enhancements larger than those obtained with NIR–NIR sequence. Compared single NIR pulse, by factors approximately 30 for Si I 288.16-nm line 100 Al II 281.62-nm were observed double total energy. This effect correlates substantial increase in plasma temperature, ionic lines having higher excitation energy experiencing enhancement. Moreover, optimal pulse separation is found be neutral (∼3 compared ∼0.1 μs). Another finding this study concerns two different wavelengths 1064 ‘mixed-wavelength’ scheme that also leads an enhanced laser-induced breakdown spectroscopy (LIBS) sensitivity. It proposed double-pulse mixed-wavelength approaches are both capable temperature enhancement reason: portion absorbed region containing atoms, instead being at sample surface or atmosphere.