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H. E. Hernandez-Figueroa

Publications and source records attributed to H. E. Hernandez-Figueroa.

4 recordsLinked to original sources

Multi-wavelength source at ITU-T grid based on ultra-flattened dispersion photonic crystal fibers

We report on the development of a multi-wavelength source locked to the ITU-T grid at 100 GHz spacing and based on ultra-flattened dispersion photonic crystal fibers. The ITU-T grid frequencies are generated by taking advantage of multiple four-wave mixing processes. We experimentally obtained 250 products spanning over 200nm by launching 03 strong pump signals. Simulations based on Split-Step Fourier Method have been carried out in order to investigate and improve the performance of this nonlinear optical device.

physics.optics↗

Theory of Frozen Waves

In this work, starting by suitable superpositions of equal-frequency Bessel beams, we develop a theoretical and experimental methodology to obtain localized stationary wave fields, with high transverse localization, whose longitudinal intensity pattern can approximately assume any desired shape within a chosen interval 0 < z < L of the propagation axis z. Their intensity envelope remains static, i.e. with velocity v=0; so that we have named ``Frozen Waves" (FW) these new solutions to the wave equations (and, in particular, to the Maxwell equations). Inside the envelope of a FW only the carrier wave does propagate: And the longitudinal shape, within the interval 0 < z < L, can be chosen in such a way that no nonnegligible field exists outside the pre-determined region (consisting, e.g., in one or more high intensity peaks). Our solutions are noticeable also for the different and interesting applications they can have, especially in electromagnetism and acoustics, such as optical tweezers, atom guides, optical or acoustic bistouries, various important medical apparata, etc.

physics.optics↗

Superluminal X-shaped beams propagating without distortion along a coaxial guide

In a previous paper [Phys. Rev. E64 (2001) 066603; e-print physics/0001039], we showed that localized Superluminal solutions to the Maxwell equations exist, which propagate down (non-evanescence) regions of a metallic cylindrical waveguide. In this paper we construct analogous non-dispersive waves propagating along coaxial cables. Such new solutions, in general, consist in trains of (undistorted) Superluminal "X-shaped" pulses. Particular attention is paid to the construction of finite total energy solutions. Any results of this kind may find application in the other fields in which an essential role is played by a wave-equation (like acoustics, geophysics, etc.). [PACS nos.: 03.50.De; 41.20;Jb; 83.50.Vr; 62.30.+d; 43.60.+d; 91.30.Fn; 04.30.Nk; 42.25.Bs; 46.40.Cd; 52.35.Lv. Keywords: Wave equations; Wave propagation; Localized beams; Superluminal waves; Coaxial cables; Bidirectional decomposition; Bessel beams; X-shaped waves; Maxwell equations; Microwaves; Optics; Special relativity; Coaxial metallic waveguides; Acoustics; Seismology; Mechanical waves; Elastic waves; Guided gravitational waves.]

physics.class-ph↗

Superluminal Localized Solutions to the wave equation, in (vacuum or) dispersive media, for arbitrary frequencies and with adjustable bandwidth

In this paper we set forth new exact analytical Superluminal localized solutions to the wave equation for arbitrary frequencies and adjustable bandwidth. The formulation presented here is rather simple, and its results can be expressed in terms of the ordinary, so-called "X-shaped waves". Moeover, by the present formalism we obtain the first analytical localized Superluminal approximate solutions which represent beams propagating in dispersive media. Our solutions may find application in different fields, like optics, microwaves, radio waves, and so on. [PACS nos.: 03.50.De ; 41.20.Jb ; 83.50.Vr ; 62.30.+d ; 43.60.+d ; 91.30.Fn ; 04.30.Nk ; 42.25.Bs ; 46.40.Cd ; 52.35.Lv. Keywords: Wave equation; Wave propagation; Optics; Localized beams; Superluminal waves; Bessel beams; X-shaped waves; Acoustics; Mechanical waves; Dispersion compensation; Seismology; Geophysics; Gravitational Waves; Elementary particle physics].

physics.class-ph↗