We demonstrate that a very recently obtained formula for the force on a slab in a material planar cavity based on the calculation of the vacuum Lorentz force [C. Raabe and D.-G. Welsch, Phys. Rev. A, 71, 013814 (2005)] describes a (medium) screened Casimir force and, in addition to it, a medium-assisted force. The latter force also describes the force on the cavity medium. For dilute media, it ...

Preferential orientation of the stripe phases in the quantum Hall (QH) regime has remained a puzzle since its discovery. We show experimentally and theoretically that the direction of high and low resistance of the two-dimensional (2D) hole gas in the QH regime can be controlled by an external strain. Depending on the sign of the in-plane shear strain, the Hartree-Fock energy of holes or electr...

Abstract: Numerical examination of the solution of the boundary–value problem of the reflection and transmission of a plane wave due to a slab of an electro–optic structurally chiral material (SCM) indicates that the exhibition of the circular Bragg phenomenon by the SCM can be controlled not only by the sign and the magnitude of a dc electric field but also by its orientation in relation to ax...

InGaN nanowires are suitable building blocks for many future optoelectronic devices. We show that a linear grading of the indium content along the nanowire axis from GaN to InN introduces an internal electric field evoking a photocurrent. Consistent with quantitative band structure simulations we observe a sign change in the measured photocurrent as a function of photon flux. This negative diff...

Parallel viscosity 〈B · ∇ ·Πi〉 as a function of radial electric field Er (or, equivalently, non equilibrium poloidal rotation) in a tokamak is studied using a 5D (3D in configuration space and 2D in velocity space) Monte Carlo particle following code. It is shown that including the poloidal density variation changes the qualitative behavior of the solution causing the parallel viscosity to chan...

We propose a model for surfaces in mixtures of oil, water, and surfactants with strong electric dipoles. The dipole interactions give rise to a non-local interaction with a negative stiffness between surface elements. We show that, for large space dimension D, this model has a phase transition from rough to smooth surfaces. Contrary to models with a simple quadratic curvature energy of a positi...

We present an adaptive P1 finite element method for two-dimensional transverse magnetic time harmonic Maxwell’s equations with general material properties and general boundary conditions. It is based on reducing the boundary value problems for Maxwell’s equations to standard second order scalar elliptic problems through the Hodge decomposition. We allow inhomogeneous and anisotropic electric pe...

We demonstrate that it is possible to combine several small metallic particles in a very compact geometry without loss of their individual modal properties by adding a gold metallic film underneath. This film essentially acts as a "ground plane" which channels the optical field of each particle and decreases the interparticle coupling. The localization of the electric field can then be controll...

A combined freeze-fracture and scanning electron microscopic study of early opaque spots in the aging human lens showed the absence of gap junctions and the presence of square arrays in the membranes of disturbed fibers and neighboring unaffected fibers. Square arrays, with membrane particles of 6-7 nm, are considered as rearranged gap junctions and/or intramembranous particles, with particle s...

A theory of the static electron polarizability of crystals whose energy spectrum is modified by quantizing magnetic fields is presented. The polarizability is strongly affected by nondissipative Hall currents induced by the presence of crossed electric and magnetic fields: these can even change its sign. Results are illustrated in detail for a two-dimensional square lattice. The polarizability ...