1,579 research outputs found
Angular and Abundance Distribution of High-energy Gamma Rays and Neutrons Simulated by GEANT4 Code for Solar Flares
In the solar flare observed on June 3, 2012, high energy gamma-rays and
neutrons were observed. The event includes a remarkable feature of a high
neutron/gamma-ratio in the secondary particles. We have examined whether this
high n/-ratio can be explained by simulation. As a result of
simulations using the GEANT4 program, the high n/-ratio may be
reproduced for the case that helium and other heavy ions were dominantly
accelerated in the flare.Comment: submitted to the Proceeding of The 20th International Symposium on
Very High Energy Cosmic Ray Interaction (ISVHECRI 2018, Nagoya, Japan),
Europian Physics Journa
Intrinsic gap and exciton condensation in the nu_T=1 bilayer system
We investigate the quasiparticle excitation of the bilayer quantum Hall (QH)
system at total filling factor in the limit of
negligible interlayer tunneling under tilted magnetic field. We show that the
intrinsic quasiparticle excitation is of purely pseudospin origin and solely
governed by the inter- and intra-layer electron interactions. A model based on
exciton formation successfully explains the quantitative behavior of the
quasiparticle excitation gap, demonstrating the existence of a link between the
excitonic QH state and the composite fermion liquid. Our results provide a new
insight into the nature of the phase transition between the two states.Comment: 4 pages, 3 figure
Simultaneous Excitation of Spins and Pseudospins in the Bilayer Quantum Hall State
The tilting angular dependence of the energy gap was measured in the bilayer
quantum Hall state at the Landau level filling by changing the density
imbalance between the two layers. The observed gap behavior shows a continuous
transformation from the bilayer balanced density state to the monolayer state.
Even a sample with 33 K tunneling gap shows the same activation energy anomaly
reported by Murphy {\it et al.}. We discuss a possible relation between our
experimental results and the quantum Hall ferromagnet of spins and pseudospins.Comment: 4 pages, 4 figure
The impacts of surface conditions on the vapor-liquid-solid growth of germanium nanowires on Si (100) substrate
The impacts of surface conditions on the growth of Ge nanowires on a Si (100) substrate are discussed in detail. On SiO2-terminated Si substrates, high-density Ge nanowires can be easily grown. However, on H-terminated Si substrates, growing Ge nanowires is more complex. The silicon migration and the formation of a native SiO2 overlayer on a catalyst surface retard the growth of Ge nanowires. After removing this overlayer in the HF solution, high-density and well-ordered Ge nanowires are grown. Ge nanowires cross vertically and form two sets of parallel nanowires. It is found that nanowires grew along ?110? direction
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