The tunnel effect is considered here within the framework of electromagnetic propagation. The classical problem of a plane gap of dielectric, surrounded on both sides by a medium with larger refraction index, is studied in the case in which an electromagnetic plane wave impinges into the gap with an incidence angle larger than the critical angle. In this condition (total reflection), the gap acts as a classically forbidden region and behaves like a tunnel. The field inside the forbidden gap consists of two evanescent waves, each one having its wavefronts normal to the interface. In the present paper we study the total field derived as a superposition of two such evanescent waves, its wavefronts, and the directions of propagation of both phase and energy.
In this paper we will analyze the propagation of the angular spectrum of the electromagnetic field through a finite length uniaxial crystal. We solve the boundary conditions of the fields at an interface of an isotropic medium and an uniaxial anisotropic medium with the optical axis in an arbitrary direction and soon after we choose the optical axis in a plane formed by the direction of propagation (z-axis) and the x-axis . We show how the couplings occur between the components of the field and in what situations we can give a vector or scalar treatment for the propagation
The quasi-one-dimensional rhombic array of the waveguides is considered. System of equations describing coupled waves in the waveguide in the linear limit is solved exactly. The electric field distribution was found both for the diffractionless (or dispersionless) flat band modes and for the dispersive modes.
In this work, we present a simplified but comprehensive derivation of all the key concepts and main results concerning light pulse propagation in dielectric media, including a brief extension to the case of active media and laser oscillation. Clarifications of the concepts of slow light and "superluminality" are provided, and a detailed discussion on the concept of transform-limited pulses is also included in the Appendix.
Pseudospin plays a central role in many novel physical properties of graphene and other artificial systems which have pseudospins of 1/2. Here we show that in certain photonic crystals (PCs) exhibiting conical dispersions at k = 0, the eigenmodes near the "Dirac-like point" can be described by an effective spin-orbit Hamiltonian with a pseudospin of 1, treating wave propagations in the upper cone, the lower cone and a flat band (corresponding to zero refractive index) within a unified framework. The 3-component spinor gives rise to boundary conditions distinct from those of pseudospin-1/2, lea…
Propagation of ultrashort electromagnetic wave packets in free space beyond the paraxial and slowly-varying-envelope approximations : a time-domain approach
We investigate electromagnetic propagation in uniaxial dielectrics with a transversely varying orientation of the optic axis, the latter staying orthogonal everywhere to the propagation direction. In such a geometry, the field experiences no refractive index gradients, yet it acquires a transversely-modulated Pancharatnam-Berry phase, that is, a geometric phase originating from a spin-orbit interaction. We show that the periodic evolution of the geometric phase versus propagation gives rise to a longitudinally-invariant effective potential. In certain configurations, this geometric phase can p…
In this paper, we present a quantum theory for field propagation through a three dimensional dielectric when the third order dispersion and the attenuation coefficients are included. A unique Lagrangian is defined leading to the correct equation of motion and the classical Hamiltonian. It is assumed that the dielectric has a combination of inhomogeneity, dispersion and nonlinearity. By employing constraint quantization approach the final Hamiltonian is expanded in terms of properly defined annihilation and creation operators. We obtain the quantum fields (quantum photon-polaritons fields) for …
The propagation of light through bianisotropic materials is studied in the geometrical optics approximation. For that purpose, we use the quartic general dispersion equation specified by the Tamm-Rubilar tensor, which is cubic in the electromagnetic response tensor of the medium. A collection of different and remarkable Fresnel (wave) surfaces is gathered, and unified via the projective geometry of Kummer surfaces.
The propagation of a quasi-harmonic electromagnetic wave in a bulk hyperbolic dielectric metamaterial is considered. If the group velocities dispersion is not taken into account, then wave propagation can be described either by the hyperbolic nonlinear Schrodinger equation or by the hyperbolic Manakov equations. It is shown that the region in the space of wave vectors in which the modulation instability of a spatially homogeneous wave is possible is not limited, in contrast to the case of ordinary media.
Wave tunneling is an intriguing phenomenon spanning different branches of physics, from quantum mechanics to classical electrodynamics and optics. The Wigner (or phase) time is proved to be an adequate measure to describe wave transit through a potential barrier or material layer in the tunneling regime. Here, we analytically and numerically calculate the Wigner time for electromagnetic-radiation propagation through the layer of both lossless and lossy plasmas. It is shown that the plasma frequency is the key parameter governing the value of Wigner time allowing us to interpret tunneling as du…
We study the propagation of three-dimensional (3D) bipolar ultrashort electromagnetic pulses in an inhomogeneous array of semiconductor carbon nanotubes. The heterogeneity is represented by a planar region with an increased concentration of conduction electrons. The evolution of the electromagnetic field and electron concentration in the sample are governed by the Maxwell's equations and continuity equation. In particular, non-uniformity of the electromagnetic field along the axis of the nanotubes is taken into account. We demonstrate that, depending on values of parameters of the electromagne…
A method is proposed for the analysis of the propagation of electromagnetic waves through a homogeneous slab of a medium with Drude-Lorentz dispersion behavior, and excited by a causal sinusoidal source. An expression of the time dependent field, free from branch-cuts in the plane of complex frequencies, is established. This method provides the complete temporal response in both the steady-state and transient regimes in terms of discrete poles contributions. The Sommerfeld and Brillouin precursors are retrieved and the corresponding set of poles are identified. In addition, the contribution in…
Free-Space Propagation and Skyrmion Topology of Toroidal Electromagnetic Pulses
Institute of Applied Physics, University of Electronic Science and Technology of China（电子科技大学应用物理研究所）；Yangtze Delta Region Institute (Huzhou), University of Electronic Science and Technology of China（电子科技大学长三角研究院（湖州））；Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University（南洋理工大学物理与数学科学学院物理学与应用物理学部）；Centre for Disruptive Photonic Technologies, The Photonics Institute, Nanyang Technological University（南洋理工大学光子研究院破坏性光子技术研究中心）；Optoelectronics Research Centre & Centre for Photonic Metamaterials, University of Southampton（南安普顿大学光电子研究中心及光子超材料中心）
We explicitly solve the equations for the propagation of an electromagnetic wave up to the subleading order geometric optics expansion in the Kerr spacetime. This is done in two nontrivial steps. We first construct a set of parallel propagated null tetrad in Kerr spacetime. Two of the components of such tetrad give the propagation and polarization of an electromagnetic wave in geometric optics approximation. Then we use the parallel propagated tetrad to solve the modified trajectory equation in Kerr spacetime. We obtain the wavelength-dependent deviation of the trajectory of electromagnetic wa…
Quantum-statistical effects occur during the propagation of electromagnetic (EM) waves inside the dielectric media or metamaterials, which include a large class of nanophotonic and plasmonic waveguides with dissipation and noise. Exploiting the formal analogy between the Schrodinger equation and the Maxwell equations for dielectric linear media, we rigorously derive the effective Hamiltonian operator which describes such propagation. This operator turns out to be essentially non-Hermitian in general, and pseudo-Hermitian in some special cases. Using the density operator approach for general no…
Analytically, without magnetostatic approximation, the problem of electromagnetic wave propagation along arbitrary direction in a tangentially magnetized bihyrotropic layer has been solved. It is found that one can bring the Maxwell equations for this problem to the fourth order differential equation and the obtained biquadratic characteristic equation determines two different wave numbers kx21 and kx22 describing the wave distribution over the layer thickness. The dispersion equation describing wave propagation in the bihyrotropic layer was obtained for the case of real kx21 and kx22 values. …
