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871.
Shaginyan V. R. Msezane A. Z. Clark J. W. Japaridze G. S. Leevik Y. S. 《JETP Letters》2020,112(10):657-665
JETP Letters - In this brief review, we address manifestations of the T/B scaling behavior of heavy-fermion (HF) compounds, where T and B are the temperature and magnetic field, respectively. Using... 相似文献
872.
JETP Letters - It has been shown that a correlated Wishart ensemble can be used to study the general vibrational properties of stable amorphous solids, where the energy is translationally... 相似文献
873.
In recent years, there is very intense worldwide research and development work on electron cyclotron resonance ion source (ECRIS). Remarkable progress represented by the third generation superconducting ECRIS has been made with regards of intense highly charged ion beam production such as >600 eμA Ar16+, >10 eμA Ar18+, and hundreds of enA He-like Kr34+. A low energy heavy ion platform named Low Energy heavy ion Accelerator Facility (LEAF) that features a next generation 45 GHz ECRIS, a 300 kV high voltage platform, a 0.5 MeV/u radio-frequency quadrupole, and several multidisciplinary experimental terminals is under construction at the Institute of Modern Physics (IMP). This paper will report on the recent progress with ECRIS dedicated to highly charged ions and the status of LEAF at IMP that will provide new opportunities for highly charged ion physics in the near future. 相似文献
874.
The propagation of phase-locked and non-phase-locked laser array beams of radial and rectangular symmetries in a turbulent
atmosphere are investigated based on the extended Huygens–Fresnel integral. The beamlet used in our paper for constructing
the laser array beams is of elliptical Gaussian mode. Analytical formulae for the average irradiance of phase-locked and non-phase-locked
radial and rectangular laser array beams are derived through vector integration and tensor operation. The irradiance properties
of these laser array beams in a turbulent atmosphere are studied numerically. It is found that both phase-locked and non-phase-locked
radial and rectangular laser array beams eventually become circular Gaussian beams in a turbulent atmosphere, which is much
different from their propagation properties in free space. The propagation properties are closely related to the parameters
of laser array beams and the structure constant of the turbulent atmosphere.
PACS 42.25.Bs; 41.85.Ew; 42.68.Ay 相似文献
875.
876.
H. B. Zhu H. X. Ge L. Y. Dong S. Q. Dai 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,57(1):103-108
Based on the Nagel-Schreckenberg (NaSch)
model of traffic flow, a modified cellular automaton (CA) traffic
model with the density-dependent randomization (abbreviated as the
DDR model) is proposed to simulate traffic flow. The fundamental
diagram obtained by simulation shows the ability of this modified
NaSch model to capture the essential features of traffic flow,
e.g., synchronized flow, metastable state, hysteresis and phase
separation at higher densities. Comparisons are made between this
DDR model and the NaSch model, also between this DDR model and the
VDR model. And the underlying mechanism is analyzed. All these
results indicate that the presented model is reasonable and more
realistic. 相似文献
877.
In a recent paper—F. Ciccarello et al., New J. Phys. 8, 214 (2006)—we have demonstrated that the electron transmission properties of a one-dimensional (1D) wire with two identical embedded spin-1/2 impurities can be significantly affected by entanglement between the spins of the scattering centers. Such an effect is of particular interest in the control of the transmission of quantum information in nanostructures and can be used as a detection scheme of maximally entangled states of two localized spins. In this letter, we relax the constraint that the two magnetic impurities are equal and investigate how the main results presented in the above paper are affected by a static disorder in the exchange coupling constants of the impurities. Good robustness against deviation from impurity symmetry is found for both the entanglement dependent transmission and the maximally entangled states generation scheme. 相似文献
878.
T.Y. Kwon Y.B. Kim K. Eom D.S. Yoon H.L. Lee T.S. Kim 《Applied Physics A: Materials Science & Processing》2007,88(4):627-632
Electrical properties of piezoelectric thick films with controlled microstructure were investigated. In order to enhance the
electromechanical properties (e.g. d31, d33) of a thick film by control of its microstructure, a mixed powder, referred to as BNP, consisting of both nano-sized and
micro-sized piezoelectric particles, was employed as a starting precursor in the film fabrication process. According to a
scanning electron microscopy study, it is shown that a BNP thick film exhibits the densest homogeneous microstructures. According
to surface area measurements, the BNP thick film was sufficiently densified without an additional infiltration process of
Pb(Zr1-xTix)O3 sol for densification. The screen-printed BNP thick film possesses a dielectric constant and a remanent polarization much
higher than those of a thick film composed of only micro-sized piezoelectric particles by a factor of more than two. This
suggests the potential application of the BNP thick film, in conjunction with a silicon substrate, to a micromachined monolithic
PZT thick film device on the silicon substrate.
PACS 85.40.Xx; 85.85.+j; 85.50.-n; 77.65.-j; 68.37.-d 相似文献
879.
X. M. Chen J. X. Shao Z. H. Yang H. Q. Zhang Y. Cui X. Xu G. Q. Xiao Y. T. Zhao X. A. Zhang Y. P. Zhang 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,41(2):281-286
Al K-shell X-ray yields are measured with highly charged Arq+ ions
(q=12–16) bombarding against aluminium. The energy range of the Ar
ions is from 180 to 380 keV. K-shell ionization cross sections of aluminium are also obtained from the yields data.
The experimental data is explained within the framework of 2pπ
-2pσ rotational coupling. When Ar ions with 2p-shell vacancies are
incident on aluminium, the vacancies begin to reduce. Meanwhile, collisions
against Al atoms lead to the production of new 2p-shell vacancies of Ar
ions. These Ar 2p-shell vacancies will transfer to the 1s orbit of an Al
atom via 2pπ-2pσ rotational coupling leading to the emission of
a K-shell X-ray of aluminiun. A model is constructed based on the base of
the above physical scenario. The calculation results of the model are in
agreement with the experimental results. 相似文献
880.
S. Chen L. Wang Y. P. Wang 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,57(3):265-270
We study the ground-state properties of frustrated Heisenberg ferrimagnetic
ladders with antiferromagnetic exchange interactions and two types of
alternating sublattice spins. In the limit of strong rung couplings, we show
that the mixed spin-1/2 and spin-1 ladders can be systematically mapped onto
a spin-1/2 Heisenberg model with additional next-nearest-neighbor exchanges.
The system is either in a ferrimagnetic state or in a critical spin-liquid
state depending on the competition between the spin exchanges along the legs
and the diagonal exchanges. 相似文献