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Abstract: In this Letter an alternative mechanism is proposed for current-induced antisymmetric lateral edge spin accumulations in thin strips of ballistic two-dimensional electron gases with intrinsic spin–orbit coupling. In this mechanism, the occurrence of current-induced antisymmetric lateral edge spin accumulations in a semiconductor strip is not due to a transverse spin current but originates from the combined action of the spin–orbit coupling, the boundary confinement on both lateral edges of the strip, and the time-reversal symmetry-breaking caused by the longitudinal charge current circulating through the strip. The results obtained in this Letter indicate that, the occurrence of current-induced antisymmetric lateral edge spin accumulations in a thin strip of a spin–orbit coupled two-dimensional electronic system does not need to be associated necessarily with a transverse spin current in principle. [Copyright &y& Elsevier]

Abstract: We propose a unified semiclassical description for the kinetic magnetoelectric effect in both k-linear and k-cubic two-dimensional Rashba model in the thermodynamic limit, which takes into account the effects of both spin coherence and spin dephasing by a closed set of Boltzman-like kinetic equations. Based on this unified description, we show that in contrary to the case found in the studies of intrinsic spin Hall effect in such systems, in the linear response regime the kinetic magnetoelectric effect would vanish for the k-cubic Rashba model in the thermodynamic limit but be robust for the k-linear Rashba model in the thermodynamic limit. [Copyright &y& Elsevier]

Abstract: Based on the three-dimensional effective Luttinger Hamiltonian and the exact Heisenberg equations of motion and within a self-consistent semiclassical approximation, we present a theoretical investigation on the nontrivial ac spin responses due to the intrinsic spin–orbit coupling of holes in p-doped bulk semiconductors. We show that the nontrivial ac spin responses induced by the combined action of an ac external electric field and the intrinsic spin–orbit coupling of holes may lead to the generation of a nonvanishing ac spin Hall current in a p-doped bulk semiconductor, which shares some similarities with the dissipationless dc spin Hall current conceived previously and also exhibits some interesting new features that was not found before. [Copyright &y& Elsevier]

Abstract: Based on a self-consistent semiclassical approach, in this Letter we try to contribute to the basic physical understanding of some controversial issues about the intrinsic spin Hall effect in a Rashba two-dimensional electron gas. We show that for a Rashba two-dimensional electron gas in the diffusive transport thermodynamic limit, there exist some simple but much clear physical reasons which explain naturally why the intrinsic spin Hall effect in such a system cannot survive in the dc limit. The physical pictures established in this Letter resolve some puzzles existed in some previous theoretical treatments about this extraordinary effect. [Copyright &y& Elsevier]

The imaging properties of uniaxially anisotropic negative refractive index materials have been investigated theoretically. Based on an accurate theoretical formulation, we have discussed in detail whether and under what conditions the slabs of uniaxially anisotropic negative refractive index materials will have the power to focus perfectly all Fourier components of an image. It was shown that if the effects of absorption and dispersion can be neglected, under some particular conditions the slabs of uniaxially anisotropic negative refractive index materials will have the power to focus perfectly all E-mode or all H-mode or both E- and H-mode Fourier components of an image. It was also shown that perfect focus cannot occur in the presence of absorption and dispersion, but if the effects of absorption and dispersion are rather small, excellent focus can still occur. [Copyright &y& Elsevier]

We study the unusual enhancement of photon tunnelling by a slab of uniaxially anisotropic negative refractive index material, also known as left-handed material (LHM). It is found that the uniaxially anisotropic LHMs can greatly enhance the photon tunnelling for transverse electric (TE), transverse magnetic (TM), as well as both TM and TE waves when different conditions are satisfied. The phenomenon is believed due to the amplification of evanescent waves by the LHMs. It is expected to find applications in devices that utilize photon tunnelling. [Copyright &y& Elsevier]