Publications by authors named "T Hosokai"

By employing the stabilizer in the supersonic gas nozzle to produce the plasma density profile with a sharp downramp, we have experimentally demonstrated highly stable electron beam acceleration based on the shock injection mechanism in laser wakefield acceleration with the use of a compact Ti:sapphire laser. A quasi-monoenergetic electron beam with a peak energy of 315 MeV ± 12.5 MeV per shot is generated.

View Article and Find Full Text PDF

Artificial molecular machines, especially when based on wheel-and-axle complexes, can generate mechanical motions in response to external stimuli. Ferrocene (Fc) is a key component, but it decomposes at 300 K on metal surfaces. Here, a novel method is presented to construct and control the molecular complex composed of ammonium-linked ferrocene (Fc-amm) and tetrabrominated crown ether (BrCR) on a Cu(111) surface.

View Article and Find Full Text PDF
Article Synopsis
  • Photon-upconversion (PUC) processes, such as triplet-triplet upconversion and hot-band absorption, are emerging for better energy harvesting but need improvements in efficiency and energy loss.* -
  • The proposed PUC mechanism utilizes a combination of a triplet sensitizer and thermally activated delayed fluorescence (TADF) molecules to efficiently transfer energy, resulting in an emission with an anti-Stokes energy of 0.18 eV.* -
  • The efficiency of this energy transfer is influenced by the radiative decay rate of TADF molecules and the Gibbs energy difference between the donor and acceptor, providing insight valuable for future applications like optical cooling systems.*
View Article and Find Full Text PDF

Although luminescent aluminum compounds have been utilized for emitting and electron transporting layers in organic light-emitting diodes, most of them often exhibit not phosphorescence but fluorescence with lower photoluminescent quantum yields in the aggregated state than those in the amorphous state due to concentration quenching. Here we show the synthesis and optical properties of β-diketiminate aluminum complexes, such as crystallization-induced emission (CIE) and room-temperature phosphorescence (RTP), and the substituent effects of the central element. The dihaloaluminum complexes were found to exhibit the CIE property, especially RTP from the diiodo complex, while the dialkyl ones showed almost no emission in both solution and solid states.

View Article and Find Full Text PDF

Organic luminescent radicals are a new class of materials with potential applications not only in light-emitting devices but also in the biochemistry field. New tris(2,4,6-trichlorophenyl)methyl (TTM) radicals with alkoxy-substituted carbazole donors were synthesized and characterized. PEG-substituted carbazole-TTM was found to be water-soluble.

View Article and Find Full Text PDF