Ali A. Kamli

Entanglement creation with negative index metamaterials

We propose a scheme for creating of a maximally entangled state comprising two field quanta. In our scheme, two weak light fields, which are initially prepared in either coherent or polarization states, interact with a composite medium near an interface between a dielectric and a negative index metamaterial. Such interaction leads to a large Kerr nonlinearity, reduction of the group velocity of the light and significant confinement of the light fields while simultaneously avoiding amplitude losses of the incoming radiation. All these considerations make our scheme efficient.

Coherent control of low loss surface polaritons.

We propose fast all-optical control of surface polaritons by placing an electromagnetically induced transparency (EIT) medium at an interface between two materials. EIT provides longitudinal compression and a slow group velocity, while matching properties of the two materials at the interface provides strong transverse confinement. In particular, we show that an EIT medium near the interface between a dielectric and a negative-index metamaterial can establish tight longitudinal and transverse confinement plus extreme slowing of surface polaritons, in both transverse electric and transverse magnetic polarizations, while simultaneously avoiding losses.

Low-loss nonlinear polaritonics

We propose a large low-loss cross-phase modulation between two coupled surface polaritons propagating through a double electromagnetically induced transparency medium situated close to a negative-index metamaterial. In particular, a mutual {pi} phase shift is attainable between the two pulses at the single-photon level.

Defeating entanglement sudden death by a single local filtering

Genuine multipartite entanglement of a quantum system can be partially destroyed by local decoherence. Is it possible to retrieve the entanglement to some extent by a single local operation? The answer to this question depends very much on the type of initial genuine entanglement. For initially pure

QUANTUM INFORMATICS WITH PLASMONIC META-MATERIALS

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A transversely localized light in a waveguide: the analytical solution and its potential application

and cluster states and if the decoherence is given by generalized amplitude damping, the answer is shown to be positive. In this case, the entanglement retrieving is achieved just by redistributing the remained entanglement of the system.

Slow light with electromagnetically induced transparency in optical fibre

Surface polaritons (SP) at a meta-material interface are proposed as qubits. The SP fields are shown to have; low losses, subwavelength confinement and can demonstrate very small modal volume. These important properties are used to demonstrate interesting applications in quantum information i.e. coherent control of weak fields, and large Kerr nonlinearity at the low photon level.

Pair correlations of dipole emitters in a finite charged-sheet structure

Investigation of light in the waveguide structures is a topical modern problem that has long historical roots. A parallel-plate waveguide is a base model in these studies and it is intensively used in numerous investigations of nanooptics, integrated circuits and nanoplasmonics. In this letter we first have found the analytical solution for the light modes in this waveguide. The solution provides a clear physical picture for description of a light within the broadband spectral range in the waveguide with various physical parameters. Potential of the analytical solutions for studies of light fields in the waveguides of nanooptics and nanoplasmonics has been also discussed.

Optical diode based on plasmonic nanosphere chains

Slow light with electromagnetically induced transparency (EIT) in the core of optical fibre containing three-level atoms is investigated. The guided modes are treated in the weakly guiding approximation which renders the analysis into a manageable form. The transparency window and permittivity profile of the core due to the strong pump field in the EIT scheme is calculated. For a specific permittivity profile of the core due to EIT, the propagation constant of the weak signal field and spatial shape of fundamental guided mode are calculated by solving the vector wave equation using the finite difference method. It is found that the transparency window and slow light field can be controlled via the optical fibre parameters. The reduced group velocity of slow light in this configuration is useful for many technological applications such as optical memories, effective control of single photon fields, optical buffers and delay lines.

Fast all-optical switch

The pair correlations arising from the cooperative emission from the joint first excited states of two identical dipole emitters localised within a finite ordered charged-sheet structure (FCSS) are investigated. The FCSS consists of a finite number of charged-sheets separating dielectric layers. The rates of de-excitation corresponding to a pair of states, namely the symmetric state and anti-symmetric state, are evaluated. The study of field-matter interactions of this kind in such a context would be useful for the development of quantum-information and the realisation of quantum-computing.