P. Martínez Vara

Generation of long-range curved-surface plasmonic modes and their propagation through thin metal films in a tandem array

We describe the generation of plasmonic modes that propagate in a curved trajectory. This is performed by masking a metal surface with two screens containing a randomly distributed set of holes that follow a Gaussian statistic. The diameter of the holes is less than the wavelength of the illuminating plane wave. By implementing scaling and rotations on each screen, we control the correlation trajectory and generate long-range curved plasmonic modes. The study is generalized for the transmission of a plasmonic mode propagating in a tandem array of thin metal films using the evanescent character of the electric field.

Topological properties of the interaction between focusing regions kind cusped

We study here the cusped-cusped interaction between two kinds of Pearcey optical fields by analyzing its topological structure. We do it in two steps; the first one is an irradiance interaction that allows us to identify organization regions. The second one is an amplitude interaction, where it is shown that the interference fringes are organized around the irradiance distribution. The topological behavior of the optical field is analyzed identifying regions with different phase functions, one of them, corresponds with a catastrophe function which has associated a focusing region, the other region can be approximated by a quadratic function. The main consequence heritage from the phase structure is interference fringes emerge from focusing regions having similar features like a topological charges. We show computational and experimental results which are in very well agreement with the theoretical model.

Analysis of wave-diffusion transitions in optical fields

ABSTRACT We analyse the local conditions for a wave optical field evolves toward diffusive behaviour, this was obtained by solving the wave-diffusion partial differential equation and identifying regions where the diffusion effects become dominant and non-dominant. Through extremal analysis, the phase function was determined to satisfy the Poisson equation, where the diffusion parameters exhibit electrically charged particle-like features in the neighbourhood of focusing regions. Additionally, the optical field exhibits a self-regulated behaviour driven by diffusion effects These features were corroborated experimentally in regions that act as a source/sinks in the interference fringes. Experimental results are shown.

Plasmon interactions kind Pearcey

The phase function of optical fields collapse on focusing regions generating a discontinuity in the amplitude function, this induces sources or sinks that corresponds with the topological charge. When the previous comments are transferred to the Plasmon optics context, the discontinuity of the electromagnetic field generates a real distribution of electric charge. This distribution has associated a geometry which can be obtained from the boundary condition of the field. A dynamical character can be implemented on the charge distribution using partial coherence processes in the illumination configuration for the synthesis of the Plasmon field, generating local current distributions modifying selectively the electromagnetic field properties. The model is performed using as a prototype the interaction between plasmon fields Pearcey and Airy kind. Both of them have associated a catastrophe function to the phase function, this mathematical representation allows us to identify and quantify the discontinuity of the electromagnetic field. The computational simulations show that the charge/current distributions present non-linear effects, which offers applications for tunable spectroscopy, plasmonic tweezers, etc.

Markovian optical modes

We describe the transition of a set of optical modes following a Markov chain process, where the mean value of the amplitude converge to a new type of partially coherent mode, with the property that the coherence features are easily tunable with the parameters of the chain. The amplitude of the resulting mode depends on the probability transition of the chain. As a prototype, we establish an analogy with gambler’s chain ruin, using as a basis for the vector space the Bessel modes of integer order. Computer simulations are shown.We describe the transition of a set of optical modes following a Markov chain process, where the mean value of the amplitude converge to a new type of partially coherent mode, with the property that the coherence features are easily tunable with the parameters of the chain. The amplitude of the resulting mode depends on the probability transition of the chain. As a prototype, we establish an analogy with gamblers chain ruin, using as a basis for the vector space the Bessel modes of integer order. Computer simulations are shown.

Partial polarization in interfered plasmon fields

We describe the polarization features for plasmon fields generated by the interference between two elemental surface plasmon modes, obtaining a set of Stokes parameters which allows establishing a parallelism with the traditional polarization model. With the analysis presented, we find the corresponding coherence matrix for plasmon fields incorporating to the plasmon optics the study of partial polarization effects.

Spatial attributes of the diffraction field

Optical diffraction fields have in general a spatial complex structure and some times can generate focusing regions, in this work we describe the focusing region associated with highly symmetric transmittances, analyzing its associated phase function. We show that generic features can be studied from a differential equation for a focusing geometry, which is obtained through angular representation for diffraction fields, according to the choice of the parameters involved, the diffraction field presents a new focusing region whose geometry and spatial evolution can be described with the only analysis of the phase singularities avoiding the integral representation.

Holographic Synthesis of Diffraction Free Beams and Dark Hollow Beams

Since its discovery, holographic techniques had been proved to be one of the most powerful tools for controlling the optical field in almost all the optical areas [1,2,3]. Just to mention some ones, these techniques had been used in the design of hybrid lenses to decrease or avoid aberrations, in optical metrology it had been used to analyze the vibration modes in order to detect potential risks. The recording of the holographic interaction on photo resins it had been possible to design surface roughness, where the statistical features of the surface can be controlled with the parameters of the recording interaction such as time of exposition, angle of recording, wavelength, etc. The influence of these parameters is manifested in the power spectrum associated to the scattered field. A very interesting application of this technique was implemented by West-O’Donnell [4] in order to describe the relation of the scattered field with surface plasmon modes. The experiment was obtained by depositing a metal thin film over the hologram surface. This technique paves the way to implement a two dimensional surface plasmon optics [5,6]. This configuration allows the study of interesting physical properties such as enhanced backscattering also the apparition of satellite peaks in the scattered field [7,8]. This process can be extended by depositing a stack of layers of dielectric thin film-metal thin film, generating in this way a holographic roughness wave guides with application to communication systems. In the holographic context, a very interesting subject consists in the research of novel material of holographic register. In this same context, recently has been reported the recording of the interaction between optical waves on rubidium vapor, which allows the control of light with light [9,10]. Other important materials of holographic register are the photorefractive crystals. In this kind of material, non-linear features can be induced and controlled. For example shift frequency, control of fluorescence time [11,12]. The purpose of this work is to present, in a plain way, the use of a photorefractive crystal as holographic recording material. The hologram consists in the interference between diffraction free beams. The interest in this topic comes from the fact that in the physical optics context, a contemporary topic research consists in the trapping and manipulation of particle conductors or/and dielectrics by means of optical fields also as atom/ion trapping