Formation and development dynamics of femtosecond laser microplasma in gases

Journal Article · Mon Jul 31 00:00:00 EDT 2006 · Quantum Electronics (Woodbury, N.Y.)

DOI:https://doi.org/10.1070/QE2006V036N07ABEH013173· OSTI ID:21466551

Bukin, V V; Vorob'ev, Nikolai S; Garnov, Sergei V; Konov, Vitalii I; Lozovoi, V I; Malyutin, A A; Shchelev, M Ya

We report our experimental investigations of the formation and development dynamics of laser plasma produced in gas microvolumes (microplasma) upon multiple ionisation by tightly focused (to a spot 2-3 {mu}m in diameter) high-intensity (up to {approx}10{sup 17} W cm{sup -2}) femtosecond pulses of a Ti:sapphire laser ({tau}{sub p} {approx_equal} 130 fs, {lambda} = 800 nm). Precision interferometric measurements (with a spatial resolution of {approx}1.5 {mu}m) were made of the spatiotemporal distribution of the refractive index and electron density in the microplasmas of the air and helium immediately during the action of the exciting femtosecond laser pulse and at the initial stage of free plasma expansion. The microplasma formation was shown to occur as a result of almost complete (up to bare nuclei) ionisation of the initial gas. For the first time the spectral continuum and the dynamics of spectral line formation in the UV and visible spectral ranges were investigated with a picosecond time resolution for the femtosecond laser-produced microplasmas of the air, N{sub 2}, Ar, and He at normal conditions. For the first time the generation of the second (even) laser radiation harmonic was recorded in a femtosecond subcritical-density plasma of gases. (special issue devoted to the 90th anniversary of a.m. prokhorov)

• OSTI ID: 21466551
• Journal Information: Quantum Electronics (Woodbury, N.Y.), Vol. 36, Issue 7; Other Information: DOI: 10.1070/QE2006v036n07ABEH013173; ISSN 1063-7818
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
ACCURACY
AIR
ELECTRON DENSITY
HELIUM
IONIZATION
LASER RADIATION
PLASMA DENSITY
PLASMA EXPANSION
PULSES
REFRACTIVE INDEX
SAPPHIRE
SPATIAL DISTRIBUTION
SPATIAL RESOLUTION
TIME RESOLUTION
CORUNDUM
DISTRIBUTION
ELECTROMAGNETIC RADIATION
ELEMENTS
EXPANSION
FLUIDS
GASES
MINERALS
NONMETALS
OPTICAL PROPERTIES
OXIDE MINERALS
PHYSICAL PROPERTIES
RADIATIONS
RARE GASES
RESOLUTION
TIMING PROPERTIES