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Results for “DIPOLES”
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Dipole spring ferroelectrics in superlattice SrTiO3/BaTiO3 thin films exhibiting constricted hysteresis loops
Ferroelectric superlattice heterostructures have recently been explored for potential applications in electronic devices. In this letter we employed the phase-field approach to simulate the domain structure and switching of a (BaTiO3)8/(SrTiO3)3 superlattice film constrained by a GdScO3 substrate. A constricted ferroelectric hysteresis loop was observed with a high saturation polarization but a small coercive field. The shape of the hysteresis loop is understood by analyzing the ferroelectric polarization distributions during switching. It is demonstrated that the constricted loop show a similar mechanism to the exchange coupling effect in magnetic multilayers.
Geometry-guided colloidal interactions and self-tiling of elastic dipoles formed by truncated pyramid particles in liquid crystals
The progress of realizing colloidal structures mimicking natural forms of organization in condensed matter is inherently limited by the availability of suitable colloidal building blocks. To enable new forms of crystalline and quasicrystalline self-organization of colloids, we develop truncated pyramidal particles that form nematic elastic dipoles with long-range electrostaticlike and geometry-guided low-symmetry short-range interactions. Using a combination of nonlinear optical imaging, laser tweezers, and video microscopy, we characterize colloidal pair interactions and demonstrate unusual forms of self-tiling of these particles into crystalline, quasicrystalline, and other arrays. Here, our findings are explained using an electrostatics analogy along with liquid crystal elasticity and symmetry breaking considerations, potentially expanding photonic and electro-optic applications of colloids.
Design evolution and properties of superconducting parallel-bar rf-dipole deflecting and crabbing cavities
Not Available
Theoretical shape of the magnetosphere boundary taking into account the geomagnetic dipole inclination to the geographic axis and the non-dipole part of the geomagnetic field
Theoretical shape of magnetosphere boundary considering inclination of geomagnetic dipole and nondipole part of geomagnetic field
An apparatus for studying electrical breakdown in liquid helium at 0.4 K and testing electrode materials for the neutron electric dipole moment experiment at the Spallation Neutron Source
In this study, we have constructed an apparatus to study DC electrical breakdown in liquid helium at temperatures as low as 0.4 K and at pressures between the saturated vapor pressure and ~600 Torr. The apparatus can house a set of electrodes that are 12 cm in diameter with a gap of 1–2 cm between them, and a potential up to ±50 kV can be applied to each electrode. Initial results demonstrated that it is possible to apply fields exceeding 100 kV/cm in a 1 cm gap between two electropolished stainless steel electrodes 12 cm in diameter for a wide range of pressures at 0.4 K. We also measured the current between two electrodes. Our initial results, I < 1 pA at 45 kV, correspond to a lower bound on the effective volume resistivity of liquid helium of ρ V > 5 × 10 18 Ω cm. This lower bound is 5 times larger than the bound previously measured. Finally, we report the design, construction, and operational experience of the apparatus, as well as initial results
Erratum to: 'Critical Behavior of Isotropic Three-Dimensional Systems with Dipole-Dipole Interactions'
No abstract prepared.
Microscopic theory of dipole–dipole interaction in ensembles of impurity atoms in a Fabry–Perot cavity
We develop a consistent quantum theory of the collective effects that take place when electromagnetic radiation interacts with a dense ensemble of impurity centers embedded in a transparent dielectric and placed in a Fabry–Perot cavity. We have calculated the spontaneous decay dynamics of an excited impurity atom as a specific example of applying the developed general theory. We analyze the dependence of the decay rate on the density of impurity centers and the sample sizes as well as on the characteristic level shifts of impurity atoms caused by the internal fields of the dielectric. We show that a cavity can affect significantly the pattern of collective processes, in particular, the lifetimes of collective states.
Deformation dependence of the isovector giant dipole resonance: The neodymium isotopic chain revisited
Not provided.
Mediating Solar Cell Performance by Controlling the Internal Dipole Change in Organic Photovoltaic Polymers
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Interfacial dipole formation and surface-electron confinement in low-coverage self-assembled thiol layers: thiophenol and p-fluorothiophenol on Cu(111)
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