Time-resolved spectroscopy characterization of femtosecond fiber laser induced plasma

摘要

This paper reports the studies on time-resolved laser induced breakdown spectroscopy (LIBS) of plasmas produced by a femtosecond (fs) fiber laser. The temporal behavior of specific ion and neutral emission lines of different materials (metals, glasses and semiconductors) has been characterized. Sub-spot-size craters are generated with near threshold pulse energy and it shows the potential for further improved spatial resolution using fs laser for LIBS application. The decay between the continuum plasma emission and the atomic emission were used as a means to maximize the signal-to-noise ratio (SNR) of the atomic emission lines for different materials. The SNR can be improved by more than one order of magnitude with optimal delay and gating. This fiber laser based LIBS can lead to a more compact, reliable, low-cost and field-deployable detection system for versatile and rapid analysis of chemical and special explosive materials.