Enhancement of optical emission was observed by laser-induced plasmas generated in the blue outer envelope of a n eutral oxy-acetylene flame. A KrF Excimer laser with a wavelength of 248 nm and a pulse duration of 23 ns was used to induce the plasmas. Fast imaging and spectra analyses were carried out to investigate plasma evolution and optical emission. The images of plasma evolution show that plasmas in flame have larger size and stronger emission intensity in the initial plasma lifetime. However, the plasma emission intensity also decays faster in flame. Spectra analyses show enhanced optical emission and narrowed line broadening from plasmas in flame. Up to 4 times of optical emission enhancement of the Al I 394.4 nm and down to 60% of its full width at half maximum (FWHM) were achieved. Moreover, the calculated electron temperature and density indicate that higher temperature and lower density plasmas were produced in the flame environment in the early plasma lifetime.

1.
Miziolect
,
A.W.
,
Palleschi
,
V.
&
Schechter
,
I.
(
2006
) Laser-Induced Breakdown Spectroscopy (LIBS):
Fundamentals and Applications
,
Cambridge University Press
,
Cambridge
.
2.
Shen
,
X.K.
,
Sun
,
J.
,
Ling
,
H.
&
Lu
,
Y.F.
(
2007
)
Spatial confinement effects in laser-induced breakdown spectroscopy
,
Applied Physics Letters
91
(
8
),
1501
.
3.
Popov
,
A.M.
,
Colao
,
F.
&
Fantoni
,
R.
(
2010
)
Spatial confinement of laser-induced plasma to enhance LIBS sensitivity for trace elements determination in soils
,
Journal of analytical atomic spectrometry
25
(
6
),
837
848
.
4.
Guo
,
L.B.
,
Li
,
C.M.
,
Hu
,
W.
&
Lu
,
Y.F.
(
2011
)
Plasma confinement by hemispherical cavity in laser-induced breakdown spectroscopy
,
Applied Physics Letters
98
(
13
),
1501
.
5.
Shen
,
X.K.
,
Lu
,
Y.F.
,
Gebre
,
T.
&
Ling
,
H.
(
2006
)
Optical emission in magnetically confined laser-induced breakdown spectroscopy
,
Journal of Applied Physics
100
(
05
),
3303
6.
Babushok
,
V.I.
,
De Lucia
,
F.C.
,
Gottfried
,
J.L.
&
Munson
,
C.A.
(
2006
)
Double pulse laser ablation and plasma: Laser induced breakdown spectroscopy signal enhancement
,
Spectrochimica Acta Part B: Atomic Spectroscopy
61
(
9
),
999
1014
.
7.
Killinger
,
D.K.
,
Allen
,
S.D.
,
Waterbury
,
R.D.
&
Stefano
,
C.
(
2007
)
Enhancement of Nd:YAG LIBS emission of a remote target using a simultaneous CO2 laser pulse
,
Optics Letters
15
(
20
),
12905
12915
.
8.
Scaffidi
,
J.
,
Pender
,
J.
,
Pearman
,
W.
&
Goode
,
S.R.
(
2003
)
Dual-pulse laser-induced breakdown spectroscopy with combinations of femtosecond and nanosecond laser pulses
,
Applied Optics
42
(
30
),
6099
6106
.
9.
Coons
,
R.W.
,
Harilal
,
S.S.
,
Hassan
,
S.M.
&
Hassanein
,
A.
(
2012
)
The importance of longer wavelength reheating in dual-pulse laser-induced breakdown spectroscopy
,
Applied Physics B: Lasers and Optics
107
,
873
880
.
10.
He
,
X.N.
,
Hu
,
W.
,
Li
,
C.M.
&
Lu
,
Y.F.
(
2011
)
Generation of high-temperature and low-density plasma for improved spectral resolutions in laser-induced breakdown spectroscopy
,
Optics Express
19
(
11
),
10997
11006
.
11.
Stratis
,
D.N.
,
Eland
,
K.L.
&
Angel
,
S.M.
(
2001
)
Effect of pulse delay time on a pre-ablation dual-pulse LIBS plasma
,
Applied Spectroscopy
55
(
10
),
1297
1303
.
12.
Sangines
,
R.
,
Sobral
,
H.
&
Alvarez-Zauco
,
E.
(
2012
)
The effect of sample temperature on the emission line intensification mechanism in orthogonal double-pulse laser induced breakdown spectroscopy
,
Spectrochimica Acta Part B: Atomic Spectroscopy
68
,
40
45
.
13.
Eschlböck-Fuchs
,
S.
,
Haslinger
,
M.J.
,
Hinterreiter
,
A.
&
Pedaring
,
J.D.
(
2013
)
Influence of sample temperature on the expansion dynamics and the optical emission of laser-induced plasma
,
Spectrochimica Acta Part B: Atomic Spectroscopy
87
,
36
42
.
14.
Tavassoli
,
S. H.
&
Gragossian
,
A.
(
2009
)
Effect of sample temperature on laser-induced breakdown spectroscopy
,
Optics & Laser Technology
41
(
4
),
481
485
.
15.
Sneddon
,
J.
,
Thiem
,
T.L.
&
Lee
,
Y.I.
(
1997
)
Lasers in Analytical Atomic Spectroscopy
,
VCH
,
New York
16.
Griem
,
H.R.
(
1974
)
Spectral Line Broadening by Plasma
,
Academic Press
.
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