Detection of trace metals in water by filament- and plasma-grating-induced breakdown spectroscopy

Abstract

Filament-and plasma-grating-induced breakdown spectroscopy (F-GIBS) was demonstrated as an efficient technique for sensitive detection of metals in water, where plasma gratings were established through synchronized nonlinear interaction of two noncollinear filaments and an additional filament was generated with another fs laser beam propagating along their bisector. A water jet was constructed vertically to the three coplanar filaments, overcoming side effects from violent plasma explosion and bubble generation. Three distinct regimes of different mechanisms were validated for nonlinear couplings of the third filament with plasma gratings. As the third filament was temporally overlapped with the two noncollinear filaments in the interaction zone, all the three filaments participated in synchronous nonlinear interaction and plasma grating structures were altered by the addition of the third filament. As the third filament was positively or negatively delayed, the as-formed plasma gratings were elongated by the delayed third filament, or plasma gratings were formed in the presence of plasma expansion of the ahead third filament, respectively. Using F-GIBS for trace metal detection in water, significant spectral line enhancements were observed.

Optimization of machine learning classification models for tumor cells based on cell elements heterogeneity with laser‐induced breakdown spectroscopy

“…Laser-induced breakdown spectroscopy (LIBS) is an atomic emission spectroscopy technique that identifies the elemental composition of a sample for quantitative and qualitative analysis [6][7][8]. The technique has the advantages of simple sample preparation, online multi-element analysis, and fast response, making it easy for clinical application and promising for cancer diagnosis and identification [9].…”

Multimodal photoacoustic imaging in analytic vulnerability of atherosclerosis

“…Hu et al. proposed a PA remote sensing microscopy method for lipid distribution characterization in biotissue in a noncontact fashion, with a broad detection bandwidth, deep penetration depth, and high signal‐to‐noise ratio [44]. A tailored high‐energy pulsed laser source with a spectrum centered at 1750 nm targets the first vibrational overtone of the C–H bond to illuminate PA signals, while a coaxial confocal continuous‐wave beam at 1550 nm is used as the probe beam.…”

Filament induced breakdown spectroscopy with enhanced excitations from plasma gratings

“…The experimental setup was similar to those used in our previous studies, [33][34][35]38,39 and the homemade lament-induced breakdown spectroscopy system is shown in Fig. 1.…”

“…They formed the plasma grating through the interaction of two non-collinear laments. Recent studies [34][35][36][37] conducted systematic comparative investigations on GIBS and laments under different conditions. The electron density of GIBS was found to be around 10 18 cm −3 in air.…”