17 research outputs found
Energy deposition dynamics of femtosecond pulses in water
We exploit inverse Raman scattering and solvated electron absorption to
perform a quantitative characterization of the energy loss and ionization
dynamics in water with tightly focused near-infrared femtosecond pulses. A
comparison between experimental data and numerical simulations suggests that
the ionization energy of water is 8 eV, rather than the commonly used value of
6.5 eV. We also introduce an equation for the Raman gain valid for ultra-short
pulses that validates our experimental procedure.Comment: 4 pages, 5 figures, submitted to Applied Physics Letter
Quantitative two-dimensional shadowgraphic set-up for high-sensitivity measurement of low-density laser-plasmas
We present a quantitative shadowgraphic method which can measure the density
of a laser-generated plasma in air with sensitivity and resolution comparable
or better than traditional interferometric techniques. Simultaneous comparison
of both shadowgraphy and interferometry has been carried out allowing the
experimental evaluation of the reliability of the shadowgraphic method
Time-resolved refractive index and absorption mapping of light-plasma filaments in water
By means of a quantitative shadowgraphic method, we performed a space-time
characterization of the refractive index variation and transient absorption
induced by a light-plasma filament generated by a 100 fs laser pulse in water.
The formation and evolution of the plasma channel in the proximity of the
nonlinear focus were observed with a 23 fs time resolution.Comment: 3 pages, 3 picture
Measurements of ultra strong fields in laser produced plasmas
EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Generation of MV/cm longitudinal terahertz electric fields from relativistic laser-solid interactions
Parametric Study of Proton Acceleration from Laser-Thin Foil Interaction
We experimentally investigated the accelerated proton beam characteristics such as maximum energy and number by varying the incident laser parameters. For this purpose, we varied the laser energy, focal spot size, polarization, and pulse duration. The proton spectra were recorded using a single-shot Thomson parabola spectrometer equipped with a microchannel plate and a high-resolution charge-coupled device with a wide detection range from a few tens of keV to several MeV. The outcome of the experimental findings is discussed in detail and compared to other theoretical works
Organic crystal-based THz source for complex refractive index measurements of window materials using single-shot THz spectroscopy
Multi-MV/cm longitudinally polarized terahertz pulses from laser–thin foil interaction
Longitudinally polarized terahertz radiation offers access to the elementary excitations and particles that cannot be addressed by transverse waves. While transverse electric fields exceeding 1 MV/cm are widely utilized for nonlinear terahertz spectroscopy, longitudinally polarized terahertz waves at this field strength are yet to be realized. In this paper, we experimentally demonstrate that by focusing radially polarized terahertz fields generated from laser–thin metallic foil interaction, longitudinally polarized terahertz with record-breaking field strength above 1.5 MV/cm can be obtained. Furthermore, we also traced the evolution of the geometric phase of the longitudinal component as it propagates through focus. A novel scheme based on noncollinear electro-optic detection has been utilized to unambiguously measure the polarization states. Our result will scale up the nonlinear spectroscopy of solid materials and particle acceleration experiments where on-axis polarization plays a crucial role.publishe
Multi-MV/cm longitudinally polarized terahertz pulses from laser–thin foil interaction
Longitudinally polarized terahertz radiation offers access to the elementary excitations and particles that cannot be addressed by transverse waves. While transverse electric fields exceeding 1 MV/cm are widely utilized for nonlinear terahertz spectroscopy, longitudinally polarized terahertz waves at this field strength are yet to be realized. In this paper, we experimentally demonstrate that by focusing radially polarized terahertz fields generated from laser–thin metallic foil interaction, longitudinally polarized terahertz with record-breaking field strength above 1.5 MV/cm can be obtained. Furthermore, we also traced the evolution of the geometric phase of the longitudinal component as it propagates through focus. A novel scheme based on noncollinear electro-optic detection has been utilized to unambiguously measure the polarization states. Our result will scale up the nonlinear spectroscopy of solid materials and particle acceleration experiments where on-axis polarization plays a crucial role.publishe