2,198 research outputs found
Disorder effect of resonant spin Hall effect in a tilted magnetic field
We study the disorder effect of resonant spin Hall effect in a two-dimension
electron system with Rashba coupling in the presence of a tilted magnetic
field. The competition between the Rashba coupling and the Zeeman coupling
leads to the energy crossing of the Landau levels, which gives rise to the
resonant spin Hall effect. Utilizing the Streda's formula within the
self-consistent Born approximation, we find that the impurity scattering
broadens the energy levels, and the resonant spin Hall conductance exhibits a
double peak around the resonant point, which is recovered in an applied titled
magnetic field.Comment: 6 pages, 4 figure
Electric field modulation of topological order in thin film semiconductors
We propose a method that can consecutively modulate the topological orders or
the number of helical edge states in ultrathin film semiconductors without a
magnetic field. By applying a staggered periodic potential, the system
undergoes a transition from a topological trivial insulating state into a
non-trivial one with helical edge states emerging in the band gap. Further
study demonstrates that the number of helical edge state can be modulated by
the amplitude and the geometry of the electric potential in a step-wise
fashion, which is analogous to tuning the integer quantum Hall conductance by a
megntic field. We address the feasibility of experimental measurement of this
topological transition.Comment: 4 pages, 4 figure
Poly[[bis(2,2-bipyridine)bis[μ6-5-(carboxylatomethoxy)benzene-1,3-dicarboxylato]trimanganese(II)] monohydrate]
The title compound, {[Mn3(C10H5O7)2(C10H8N2)2]·H2O}n, was synthesized under hydrothermal conditions. Six carboxylate groups of six 5-(carboxylatomethoxy)benzene-1,3-dicarboxylate anions (OABDC3−) join three MnII ions into a trinuclear centrosymmetric [Mn3(μ2-COO)6] unit with one Mn site situated on a centre of inversion. The latter MnII ion exhibits a distorted MnO6 coordination, whereas the other MnII ion has a trigonal–bipyramidal MnN2O3 coordination environment resulting from three carboxylate O atoms and the two N atoms of the bipyridine ligand. Adjacent units are linked to each other by OABDC3− ligands into a layer parallel to (010). Within the layer, O—H⋯O hydrogen-bonding interactions involving the uncoordinated and half-occupied water molecule and the free carboxylate O atoms are observed. The layers stack along [010], constructing a three-dimensional structure through π–π interactions between adjacent pyridine rings, with a centroid–centroid distance of 3.473 (5) Å
Quantum criticality at infinite temperature
Quantum criticality, being important as an indicator of new quantum matters
emerging, is known to occur only at zero or low temperature. We find that a
quantum probe, if its coherence time is long, can detect quantum criticality at
infinitely high temperature. In particular, the echo control over a spin probe
can remove the thermal fluctuation effects and hence reveals the quantum
fluctuation effects. Probes with quantum coherence time of milliseconds or
seconds can be used to study emerging quantum orders that would occur at
extremely low temperatures of nano- or pico-Kelvin. This discovery establishes
a physical link between time and inverse temperature and provides a new route
to the wonderland of quantum matters.Comment: 4 pages 4 figure
BGO quenching effect on spectral measurements of cosmic-ray nuclei in DAMPE experiment
The Dark Matter Particle Explorer (DAMPE) is a satellite-borne detector
designed to measure high energy cosmic-rays and -rays. As a key
sub-detector of DAMPE, the Bismuth Germanium Oxide (BGO) imaging calorimeter is
utilized to measure the particle energy with a high resolution. The nonlinear
fluorescence response of BGO for large ionization energy deposition, known as
the quenching effect, results in an under-estimate of the energy measurement
for cosmic-ray nuclei. In this paper, various models are employed to
characterize the BGO quenching factors obtained from the experimental data of
DAMPE. Applying the proper quenching model in the detector simulation process,
we investigate the tuned energy responses for various nuclei and compare the
results based on two different simulation softwares, i.e. GEANT4 and FLUKA. The
BGO quenching effect results in a decrease of the measured energy by
approximately () for carbon (iron) at 10 GeV/n and
above 1 TeV/n, respectively. Accordingly, the correction of the BGO quenching
effect leads to an increase of the low-energy flux measurement of cosmic-ray
nuclei.Comment: 13 pages, 4 figures, to be published in Nuclear Inst. and Methods in
Physics Research,
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