1,918 research outputs found
Stochastic Rotation Dynamics for Nematic Liquid Crystals
We introduce a new mesoscopic model for nematic liquid crystals (LCs). We
extend the particle-based stochastic rotation dynamics method, which reproduces
the Navier-Stokes equation, to anisotropic fluids by including a simplified
Ericksen-Leslie formulation of nematodynamics. We verify the applicability of
this hybrid model by studying the equilibrium isotropic-nematic phase
transition and nonequilibrium problems, such as the dynamics of topological
defects, and the rheology of sheared LCs. Our simulation results show that this
hybrid model captures many essential aspects of LC physics at the mesoscopic
scale, while preserving microscopic thermal fluctuations
Simulating broken -symmetric Hamiltonian systems by weak measurement
By embedding a -symmetric (pseudo-Hermitian) system into a large
Hermitian one, we disclose the relations between -symmetric
Hamiltonians and weak measurement theory. We show that the amplification effect
in weak measurement on a conventional quantum system can be used to effectively
simulate a local broken -symmetric Hamiltonian system, with the
pre-selected state in the -symmetric Hamiltonian system and its
post-selected state resident in the dilated Hamiltonian system.Comment: 4 pages; with Supplemental Materia
Solvable dilation model of -symmetric systems
The dilation method is a practical way to experimentally simulate
non-Hermitian, especially -symmetric quantum systems. However, the
time-dependent dilation problem cannot be explicitly solved in general. In this
paper, we present a simple yet non-trivial exactly solvable dilation problem
with two dimensional time-dependent -symmetric Hamiltonian. Our system
is initially set in the unbroken -symmetric phase and later goes
across the so-called exceptional point and enters the broken -symmetric phase. For this system, the dilated Hamiltonian and the evolution
of -symmetric system are analytically worked out. Our result clearly
showed that the exceptional points do not have much physical relevance in a
\textit{time-dependent} system.Comment: 9 pages, 4 figures, close to the published versio
Multi-domain vertical alignment liquid crystal displays with improved angular dependent gamma curves.
Methods, systems and apparatus for a liquid crystal display panel having a first substrate with a color filter, an over-coating and a common electrode. The second substrate includes an insulating layer surface facing the first substrate, a pixel electrode, a plurality of common and pixel domain guides formed on the common and the pixel electrodes, a plurality of electric shields on one of the common or pixel electrodes and a liquid crystal layer vertically aligned between the first and second substrates. The panel also includes a drive circuit for applying a voltage to generate an electric field to control liquid crystal molecule orientation corresponding to the plurality of domain guides and electric shields to form a multi-domain liquid crystal display panel device. The plural domain guides are either protrusions or slits formed in the common electrode and the pixel electrode to form the multi-domain vertical alignment liquid crystal device
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