Open AccessTwo-dimensional fluorescence spectroscopy of laser-produced plasmas
Author(s) -
S. S. Harilal,
N. L. LaHaye,
Mark C. Phillips
Publication year - 2016
Publication title -
optics letters/optics index
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.524
H-Index - 272
eISSN - 1071-2763
pISSN - 0146-9592
DOI - 10.1364/ol.41.003547
Subject(s) - laser , materials science , emission spectrum , spectroscopy , absorption spectroscopy , excited state , laser induced fluorescence , absorption (acoustics) , laser ablation , atomic physics , fluorescence spectroscopy , plasma , ultrafast laser spectroscopy , laser induced breakdown spectroscopy , tunable diode laser absorption spectroscopy , fluorescence , sapphire , spectral line , optics , physics , quantum mechanics , astronomy , composite material
We use a two-dimensional laser-induced fluorescence spectroscopy technique to measure the coupled absorption and emission properties of atomic species in plasmas produced via laser ablation of a solid aluminum target at atmospheric pressure. Emission spectra from the Al I 394.4 nm and Al I 396.15 nm transitions are measured while a frequency-doubled, continuous wave (cw) Ti:sapphire laser is tuned across the Al I 396.15 nm transition. The resulting two-dimensional spectra show the energy coupling between the two transitions via increased emission intensity for both transitions during resonant absorption of the cw laser at one transition. Time-delayed, gated detection of the emission spectrum is used to isolate resonantly excited fluorescence emission from thermally excited emission from the plasma. In addition, the tunable cw laser measures the absorption spectrum of the Al transition with ultrahigh resolution after the plasma has cooled, resulting in narrower spectral linewidths than observed in emission spectra. Our results highlight that fluorescence spectroscopy employing cw laser re-excitation after pulsed laser ablation combines benefits of both traditional emission and absorption spectroscopic methods.