1,013 research outputs found
Temperature Dependence of Photoelectrical Properties of Single Selenium Nanowires
Influence of temperature on photoconductivity of single Se nanowires has been studied. Time response of photocurrent at both room temperature and low temperature suggests that the trap states play an important role in the photoelectrical process. Further investigations about light intensity dependence on photocurrent at different temperatures reveal that the trap states significantly affect the carrier generation and recombination. This work may be valuable for improving the device optoelectronic performances by understanding the photoelectrical properties
The mutual diffusion coefficient for (meth)acrylate monomers as determined with a nuclear microprobe
Room temperature plasmon laser by total internal reflection
Plasmon lasers create and sustain intense and coherent optical fields below
light's diffraction limit with the unique ability to drastically enhance
light-matter interactions bringing fundamentally new capabilities to
bio-sensing, data storage, photolithography and optical communications.
However, these important applications require room temperature operation, which
remains a major hurdle. Here, we report a room temperature semiconductor
plasmon laser with both strong cavity feedback and optical confinement to
1/20th of the wavelength. The strong feedback arises from total internal
reflection of surface plasmons, while the confinement enhances the spontaneous
emission rate by up to 20 times.Comment: 8 Page, 2 Figure
Search for C-parity violation in and
Using events recorded in
collisions at 3.686 GeV with the BESIII at the BEPCII collider, we
present searches for C-parity violation in and decays via . No significant
signals are observed in either channel. Upper limits on the branching fractions
are set to be and
at the 90\%
confidence level. The former is one order of magnitude more stringent than the
previous upper limit, and the latter represents the first limit on this decay
channel.Comment: 7 pages, 2 figure
Measurement of the final states , , and from \psip electromagnetic decays and \ee annihilations
Cross sections and form factors for \ee \to \wpi, , and
\rho\etap at center of mass energies of 3.650, 3.686, and 3.773 GeV are
measured using data samples collected with the BESII detector at the BEPC.
Also, the branching fractions of \psi(2S) \rar \wpi, , and
\rho\etap are determined to be ,
, and
, respectively.Comment: 8 pages, 4 figures, 4 table
Observation of the state in at BESIII
We report the observation of the in the process with a statistical
significance of , in data samples at center-of-mass energies
4.230, 4.260, 4.360, 4.420 and 4.600~GeV collected with the BESIII
detector at the BEPCII electron positron collider. The measured mass of the
is ~MeV/, where the first error is
statistical and the second systematic, and the width is less than ~MeV at
the 90\% confidence level. The products of the Born cross sections for
and the branching ratio are also measured. These measurements are in good
agreement with the assignment of the as the charmonium
state.Comment: 7 pages, 3 figures, version to appear in Phys. Rev. Let
Measurement of the proton form factor by studying
Using data samples collected with the BESIII detector at the BEPCII collider,
we measure the Born cross section of at 12
center-of-mass energies from 2232.4 to 3671.0 MeV. The corresponding effective
electromagnetic form factor of the proton is deduced under the assumption that
the electric and magnetic form factors are equal . In
addition, the ratio of electric to magnetic form factors, , and
are extracted by fitting the polar angle distribution of the proton
for the data samples with larger statistics, namely at 2232.4 and
2400.0 MeV and a combined sample at = 3050.0, 3060.0 and 3080.0 MeV,
respectively. The measured cross sections are in agreement with recent results
from BaBar, improving the overall uncertainty by about 30\%. The
ratios are close to unity and consistent with BaBar results in
the same region, which indicates the data are consistent with the
assumption that within uncertainties.Comment: 13 pages, 24 figure
Observation of the Dalitz Decay
We report the first observation of the Dalitz decay , based on a data sample of 1.31 billion events collected with
the BESIII detector. The mesons are produced via the decay process. The ratio is measured to be
. This
corresponds to a branching fraction . The transition form
factor is extracted and different expressions are compared to the measured
dependence on the invariant mass. The results are consistent with the
prediction of the Vector Meson Dominance model.Comment: 11 pages,7 figure
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