Energy Dependence of Emission Intensity and Temperature in a LIBS Plasma Using Femtosecond Excitation

Abstract

In this paper, we investigate the effect of laser energy on laser-induced breakdown emission intensity and average temperature in a short-pulse plasma generated by using 140 fs laser excitation. Both line emission and continuum background intensity and plasma temperature decrease very rapidly after excitation compared to the more conventional nanosecond pulse excitation. Both emission intensity and plasma temperature increase with increasing laser energy. However, the intensity increase appears to be mostly related to the amount of material ablated. Also, nongated laser-induced breakdown spectroscopy (LIBS) is demonstrated using a high-pulse (1 kHz) pulse repetition rate.

Evaluation of Femtosecond Laser-Induced Breakdown Spectroscopy for Analysis of Animal Tissues

“…At 140 ns, ion lines are weak while the atomic lines present a slower decay on emission intensity. This fast plasma time evolution agrees with the data previously reported by Eland et al 40 when using fs-LIBS for analysis of steel and glass and with Baudelet et al, 29 who recently compared nanosecond and femtosecond LIBS for bacteria analysis. As a compromise, in order to provide high signal-tobackground ratios (SBR), an 80 ns delay time was chosen for further measurements.…”

Multianalytical characterization of Late Roman glasses including nanosecond and femtosecond laser induced breakdown spectroscopy

“…2 Although many studies have been undertaken to investigate the influence of these factors, there is relatively less knowledge available about the influence of laser pulse duration on LIBS analysis. [14][15][16] With the introduction of ultra-short laser pulses in the picosecond (ps) and femtosecond (fs) ranges, a large interest in investigating the advantages offered by these laser sources for spectrometric applications, such as LIBS, has been developed both in single or double pulse approaches. 14,[17][18][19][20] The physical mechanisms involved in ultrashort fs laser ablation differ from those taking place with nanosecond (ns) pulses.…”

“…[14][15][16] With the introduction of ultra-short laser pulses in the picosecond (ps) and femtosecond (fs) ranges, a large interest in investigating the advantages offered by these laser sources for spectrometric applications, such as LIBS, has been developed both in single or double pulse approaches. 14,[17][18][19][20] The physical mechanisms involved in ultrashort fs laser ablation differ from those taking place with nanosecond (ns) pulses. Because of their very short duration, fs pulses do not interact with the resulting plasma; thus the absorbed laser energy is fully deposited into the material at the solid density, with little thermal diffusion while the pulse is on.…”

Laser assisted plasma spectrochemistry: laser ablation

“…Several studies have explored the use of ultrashort (ps and fs) pulsed lasers for LIBS. 62,[84][85][86][87][88] The spatial extent, growth and decay of ionic and atomic emission lines were significantly different for femtosecond LIBS. Plasma temperature and electron number density are shown for femtosecond and nanosecond pulsed LIBS (Fig.…”