A compact, high-efficiency, quasi-continuous wave mini-stack diode pumped, actively Q-switched laser source for laser-induced breakdown spectroscopy

During recent years, the development of portable laser-induced breakdown spectroscopy (LIBS) instruments has emerged as a very active research field, taking advantage of the known characteristics of this technique for in situ measurements. The development of new, compact, robust and affordable laser sources that can be easily assembled in portable or handheld LIBS systems is of great interest for several fields of application. This article presents the design and characterization of a quasi-continuous wave (QCW) diode pumped Nd:YAG laser with a reduced size. The use of QCW diodes as a pumping source allows to obtain a compact laser with good efficiency and low power consumption. The laser presented here provides good results in terms of beam quality, pulse energy, repeatability and pulse durations, allowing the deposition of enough energy in a small area, and providing enough fluence to carry out a LIBS analysis in most solid materials. Furthermore, the integration of the proposed laser source in a handheld or lab LIES system is shown here. Several measurements using the different LIES configurations are presented to show the suitability of the proposed design for analytical applications.