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A theoretical study of one-dimensional heterostructures composed of alternate layers of a Kerr polaritonic material and a linear dispersive metamaterial is performed. For frequency values at the edges of the non-Bragg zero- ϕ eff gap of the heterostructure in the linear regime, a switching from very low to high transmission states is obtained and localized gap solitons of various orders are found, depending on the particular value of the incident power. Soliton solutions are shown to be robust with respect to absorption effects and a study is presented for gap soliton phases at the top and bottom of the zero- ϕ eff gap in the case of defocusing and focusing nonlinearities.

The transmission properties of electromagnetic waves through a one-dimensional layered system containing alternate layers of air and a uniaxial anisotropic left-handed material are investigated. The optical axis of such heterostructure is along the stacking direction and the components of the electric permittivity and magnetic permeability tensors that characterize the metamaterial are modeled by a Drude-type response and a split-ring resonator metamaterial response, respectively. Different plasmon frequencies are considered for directions parallel and perpendicular to the optical axis. For oblique incidence, longitudinal bulk-like plasmon polariton modes are found in the neighborhood of the plasmon frequency along the optical axis and anisotropy leads to the unfolding of nearly dispersionless plasmon–polariton bands either above or below the plasmon frequency. Moreover, it is shown that, even in the presence of loss/absorption, these plasmon polariton modes do survive and, therefore, should be experimentally detected.

The effective electron Lande factor in GaAs – Ga 1 - x Al x As rectangular quantum well wires, under magnetic fields applied along the wire axis, is studied by taking into account the non-parabolicity and anisotropy of the conduction band within the Ogg–McCombe effective Hamiltonian. Confinement effects on the electron wavefunctions are explored in order to evaluate its influence on the behavior of the effective Lande factor. Calculations for the electron g ∥ factor in GaAs – Ga 1 - x Al x As rectangular quantum well wires are compared with the previous theoretical results obtained for GaAs – Ga 1 - x Al x As cylindrical quantum well wires. Such comparison clearly indicates the influence of the wire shape on the electron Lande factor in GaAs – Ga 1 - x Al x As quantum well wires.

We have used the fractional-dimensional space approach to study the effects of applied magnetic fields on shallow-impurity states in GaAs–(Ga,Al)As quantum wells and superlattices. In this scheme, a semiconductor heterostructure is treated as isotropic in an effective fractional-dimensional space, and the value of the fractional dimension is associated to the degree of anisotropy introduced both by the heterostructure barrier potential and applied magnetic field. Theoretical fractional-dimensional calculations for shallow-impurity states in GaAs–(Ga,Al)As semiconductor quantum wells and superlattices, under magnetic fields applied along the growth direction, were shown to be in overall agreement with available experimental measurements and previous variational calculations.

We use the Ogg–McCombe Hamiltonian together with the Dresselhaus and Rashba spin-splitting terms to find the g factor of conduction electrons in GaAs-(Ga,Al)As semiconductor quantum wells (QWS) (either symmetric or asymmetric) under a magnetic field applied along the growth direction. The combined effects of non-parabolicity, anisotropy and spin-splitting terms are taken into account. Theoretical results are given as functions of the QW width and compared with available experimental data and previous theoretical works.