22,520 research outputs found
Gluon saturation and pseudo-rapidity distributions of charged hadrons at RHIC energy regions
We modified the gluon saturation model by rescaling the momentum fraction
according to saturation momentum and introduced the Cooper-Frye hydrodynamic
evolution to systematically study the pseudo-rapidity distributions of final
charged hadrons at different energies and different centralities for Au-Au
collisions in relativistic heavy-ion collisions at BNL Relativistic Heavy Ion
Collider (RHIC). The features of both gluon saturation and hydrodynamic
evolution at different energies and different centralities for Au-Au collisions
are investigated in this paper.Comment: 14 pages, 4 figure
Charge transport in underdoped bilayer cuprates
Within the t-J model, we study the charge transport in underdoped bilayer
cuprates by considering the bilayer interaction. Although the bilayer
interaction leads to the band splitting in the electronic structure, the
qualitative behavior of the charge transport is the same as in the case of
single layer cuprates. The conductivity spectrum shows a low-energy peak and
the unusual midinfrared band. This midinfrared band is suppressed severely with
increasing temperatures, while the resistivity in the heavily underdoped regime
is characterized by a crossover from the high temperature metallic-like to the
low temperature insulating-like behaviors, which are consistent with the
experiments.Comment: 5 pages, Revtex, three figures are include
A gauge invariant dressed holon and spinon description of the normal-state of underdoped cuprates
A partial charge-spin separation fermion-spin theory is developed to study
the normal-state properties of the underdoped cuprates. In this approach, the
physical electron is decoupled as a gauge invariant dressed holon and spinon,
with the dressed holon behaving like a spinful fermion, and represents the
charge degree of freedom together with the phase part of the spin degree of
freedom, while the dressed spinon is a hard-core boson, and representing the
amplitude part of the spin degree of freedom. The electron local constraint for
single occupancy is satisfied. Within this approach, the charge and spin
dynamics of the underdoped cuprates are studied based on the t-t'-J model. It
is shown that the charge dynamics is mainly governed by the scattering from the
dressed holons due to the dressed spinon fluctuation, while the scattering from
the dressed spinons due to the dressed holon fluctuation dominates the spin
dynamics.Comment: 10 pages, 7 figures, corrected typo
A conceptual framework for interactive virtual storytelling
This paper presents a framework of an interactive storytelling system. It can integrate five components: management centre, evaluation centre, intelligent virtual agent, intelligent virtual environment, and users, making possible interactive solutions where the communication among these components is conducted in a rational and intelligent way. Environment plays an important role in providing heuristic information for agents through communicating with the management centre. The main idea is based on the principle of heuristic guiding of the behaviour of intelligent agents for guaranteeing the unexpectedness and consistent themes
Enhanced spin injection efficiency in a four-terminal double quantum dot system
Within the scheme of quantum rate equations, we investigate the spin-resolved
transport through a double quantum dot system with four ferromagnetic
terminals. It is found that the injection efficiency of spin-polarized
electrons can be significantly improved compared with single dot case. When the
magnetization in one of four ferromagnetic terminals is antiparallel with the
other three, the polarization rate of the current through one dot can be
greatly enhanced, accompanied by the drastic decrease of the current
polarization rate through the other one. The mechanism is the exchange
interaction between electrons in the two quantum dots, which can be a promising
candidate for the improvement of the spin injection efficiency.Comment: 10 pages and 5 figure
- …