A5048017432- Laser-Plasma Interactions and Diagnostics
- Laser-induced spectroscopy and plasma
- Laser-Matter Interactions and Applications
- Cold Atom Physics and Bose-Einstein Condensates
- Advanced Frequency and Time Standards
- High-pressure geophysics and materials
- Atomic and Molecular Physics
- Nuclear Physics and Applications
- Quantum optics and atomic interactions
- Atomic and Subatomic Physics Research
- Particle Accelerators and Free-Electron Lasers
- Gyrotron and Vacuum Electronics Research
Osaka University
2004-2013
Institute for Laser Technology
2007
We report an observation of surface acceleration fast electrons in intense laser-plasma interactions. When a preformed plasma is presented front solid target with higher laser intensity, the emission direction changed to from and specular directions. This feature could be caused by formation strong static magnetic field along which traps holds on surface. In our experiment, increase intensity due relativistic self-focusing plays important role for formation. The strength calculated bent...
Abstract For the first time, we experimentally determine infrared magic wavelength for 40 Ca + <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:mn>4</mml:mn> <mml:mi>s</mml:mi> <mml:msup> <mml:mstyle scriptlevel="0"/> <mml:mn>2</mml:mn> </mml:msup> </mml:mrow> <mml:msub> <mml:mi>S</mml:mi> <mml:mn>1</mml:mn> <mml:mo>/</mml:mo> </mml:msub> <mml:mo accent="false" stretchy="false">→</mml:mo> <mml:mn>3</mml:mn> <mml:mi>d</mml:mi> <mml:mi>D</mml:mi>...
The characteristics of the forward hot electrons produced by subpicosecond laser-plasma interactions are studied for different laser polarizations at intensities from subrelativistic to relativistic. peak electron beam p-polarized shifts propagation direction target normal as intensity reaches For s-polarized pulse, mainly directed axis direction. temperature and maximum energy much higher than that expected empirical scaling law. spectra evolve be a single-temperature structure relativistic...
Ion acceleration inside low-density foams irradiated by ultraintense laser pulses has been studied experimentally and theoretically. It is found that the ion generation closely correlated with suppressed hot electron transport foams. Particle-in-cell simulations suggest localized electrostatic fields multi peaks around surfaces of lamellar layers are induced. These inhibit meanwhile accelerate ions foams, forming a bulk in contrast to surface at front rear sides thin solid target.
Energetic electrons and protons are observed when a target consisting of reentrant cone with disk at the tip is irradiated by petawatt (PW) laser an intensity approximately 10(19) W cm(-2). The angular distribution protons, dependent on open angle cone, found to differ from that in case planar geometry used. Two jet beams observed, directions parallel axis normal cone-shaped wall. number cutoff energies generated also related cone. efficiency generation energetic 2-3 times higher than simple...
A large number of hot electrons exceeding the Alfvén current can be produced when an ultraintense laser pulse irradiates a solid target. Self-excited extreme electrostatic and magnetic fields at target rear could influence electron trajectory. In order to investigate influence, we measure plasma was created on surface in advance observe increase by factor 2. This may due changes potential formation process with plasma. Using one-dimensional particle-in-cell simulation, it is shown that...
We observe a hollow structure and fine ring in the proton images from petawatt scale laser interaction with ``cone-fiber'' target. The protons related to are accelerated cone-tip surface deflected later by radial electric field surrounding fiber. Those associated fiber this field. This is found decay exponentially within 3 ps about $5\ifmmode\times\else\texttimes\fi{}{10}^{12}\text{ }\text{ }\mathrm{V}/\mathrm{m}$. Two-dimensional particle-in-cell simulations produce similar angular distributions.
Abstract We have experimentally achieved the all-optical trapping of a 40 Ca + ion for first time. An optical dipole trap was established using high-power, far-detuned, tightly focused laser with wavelength 532 nm. The single trapped without any radio-frequency (RF) fields and demonstrated long lifetime over 3 seconds. In this experiment, we implemented several measures to improve probability, including focusing beam waist near diffraction limit, precisely compensating stray electric fields,...
For the first time, we experimentally determine infrared magic wavelength for 40Ca+ 4s2S1/2 ➡ 3d2D5/2 electric quadrupole transition by observation of light shift canceling in optical clock. A "magic" magnetic field direction is chosen to make insensitive both linear polarization purity and laser. The determined this 1056.37(9) nm, which not only good agreement with theoretical predictions but also more precise a factor about 300. Using measured derive differential static polarizability be...
Near-infrared radiation is experimentally observed by coupling a grating to the electron beams generated in laser-solid target interaction. Such kinds of hold promise for tunable compact "table-top" powerful Tera-Hertz source.
Near-infrared radiation with wavelength around 1000 nm is experimentally observed by coupling a periodical metal grating to the MeV electron beams high current density generated in intense ultra short pulse laser and solid target interaction. Simulations prove prospect of tuning such kinds into sub-mm waves, which holds promise for tunable compact "table-top" powerful Tera-Hertz source.