Broadband isotropic μ-near-zero metamaterials

Natural diamagnetism, while being a common phenomenon, is limited to permeability values close to unity. Artificial diamagnetics, to the contrary, can be engineered to provide much lower values and may even possess an effective permeability close to zero. In this letter, we provide an experimental confirmation of the possibility to obtain extremely low permeability values by manufacturing an isotropic metamaterial composed of conducting cubes. We show that the practical assembly is quite sensitive to fabrication tolerances and demonstrate that permeability of about μ=0.15 is realisable.This work was supported by the Ministry of Education and Science of Russian Federation (Project 11.G34.31.0020), Dynasty Foundation (Russia), grant of the President of Russian Federation, and by the Australian Research Council (CUDOS Centre of Excellence CE110001018)

Nonlinear interaction of meta-atoms through optical coupling

We propose and experimentally demonstrate a multi-frequency nonlinear coupling mechanism between split-ring resonators. We engineer the coupling between two microwave resonators through optical interaction, whilst suppressing the direct electromagnetic coupling. This allows for a power-dependent interaction between the otherwise independent resonators, opening interesting opportunities to address applications in signal processing, filtering, directional coupling, and electromagnetic compatibility.This work was supported by the Ministry of Education and Science of Russian Federation (Project No. 11.G34.31.0020), Russian Foundation for Basic Research (Projects No. 13-02-00411 and 14-02-31783), Scholarship of the President of the Russian Federation for young scientists and graduate students, and by the Australian Research Council (CUDOS Centre of Excellence CE110001018). A.P.S. acknowledges the support of SPIE Scholarship 2012-2013 and the IEEE MTT-S Undergraduate Scholarship for spring 2013. A.P.S. and D.S.F. are also grateful to the “Dynasty” Foundation (Russia)

Magnetoelastic nonlinear metamaterials

We introduce the concept of magnetoelastic metamaterials with electromagnetic properties depending on elastic deformation. We predict a strong nonlinear and bistable response of such metamaterials caused by their structural reshaping in response to the applied electromagnetic field. In addition, we demonstrate experimentally the feasibility of the predicted effect.Comment: 4 pages, 5 figure

Una visión arquitectónica de sistema para aplicaciones en domótica

En el presente paper se ilustra una arquitectura de sistema para el control y monitoreo de módulos domóticos. Por una parte, la arquitectura de software se centra en un ambiente distribuido homogéneo pudiendo acceder a la funcionalidad de módulos domóticos, por medio de una Intranet o Internet. Por otra parte, se emplea una arquitectura distribuida CAN (Controller Area Network) en cuanto a la infraestructura para acceder a los dispositivos de sensado y actuación. Debido a que en trabajos anteriores se ha discutido la arquitectura de software, en este paper nos centraremos en las interfaces, capas y nodos funcionales para programar, controlar y monitorear un edificio así llamado inteligente. Se presenta consideraciones finales y futuros avances en el empleo de arquitecturas de software y hardware con potencial repercusión para el campo de la Domótica, entre otros dominios.Eje: Sistemas operativosRed de Universidades con Carreras en Informática (RedUNCI

Una visión arquitectónica de sistema para aplicaciones en domótica

En el presente paper se ilustra una arquitectura de sistema para el control y monitoreo de módulos domóticos. Por una parte, la arquitectura de software se centra en un ambiente distribuido homogéneo pudiendo acceder a la funcionalidad de módulos domóticos, por medio de una Intranet o Internet. Por otra parte, se emplea una arquitectura distribuida CAN (Controller Area Network) en cuanto a la infraestructura para acceder a los dispositivos de sensado y actuación. Debido a que en trabajos anteriores se ha discutido la arquitectura de software, en este paper nos centraremos en las interfaces, capas y nodos funcionales para programar, controlar y monitorear un edificio así llamado inteligente. Se presenta consideraciones finales y futuros avances en el empleo de arquitecturas de software y hardware con potencial repercusión para el campo de la Domótica, entre otros dominios.Eje: Sistemas operativosRed de Universidades con Carreras en Informática (RedUNCI

Nonlinear Localization in Metamaterials

Metamaterials, i.e., artificially structured ("synthetic") media comprising weakly coupled discrete elements, exhibit extraordinary properties and they hold a great promise for novel applications including super-resolution imaging, cloaking, hyperlensing, and optical transformation. Nonlinearity adds a new degree of freedom for metamaterial design that allows for tuneability and multistability, properties that may offer altogether new functionalities and electromagnetic characteristics. The combination of discreteness and nonlinearity may lead to intrinsic localization of the type of discrete breather in metallic, SQUID-based, and ${\cal PT}-$symmetric metamaterials. We review recent results demonstrating the generic appearance of breather excitations in these systems resulting from power-balance between intrinsic losses and input power, either by proper initialization or by purely dynamical procedures. Breather properties peculiar to each particular system are identified and discussed. Recent progress in the fabrication of low-loss, active and superconducting metamaterials, makes the experimental observation of breathers in principle possible with the proposed dynamical procedures.Comment: 19 pages, 14 figures, Invited (Review) Chapte

Metadevice for intensity modulation with sub-wavelength spatial resolution

Effectively continuous control over propagation of a beam of light requires light modulation with pixelation that is smaller than the optical wavelength. Here we propose a spatial intensity modulator with sub-wavelength resolution in one dimension. The metadevice combines recent advances in reconfigurable nanomembrane metamaterials and coherent all-optical control of metasurfaces. It uses nanomechanical actuation of metasurface absorber strips placed near a mirror in order to control their interaction with light from perfect absorption to negligible loss, promising a path towards dynamic beam diffraction, light focusing and holography without unwanted diffraction artefacts

Child/Adolescent Anxiety Multimodal Study (CAMS): rationale, design, and methods

<p>Abstract</p> <p>Objective</p> <p>To present the design, methods, and rationale of the Child/Adolescent Anxiety Multimodal Study (CAMS), a recently completed federally-funded, multi-site, randomized placebo-controlled trial that examined the relative efficacy of cognitive-behavior therapy (CBT), sertraline (SRT), and their combination (COMB) against pill placebo (PBO) for the treatment of separation anxiety disorder (SAD), generalized anxiety disorder (GAD) and social phobia (SoP) in children and adolescents.</p> <p>Methods</p> <p>Following a brief review of the acute outcomes of the CAMS trial, as well as the psychosocial and pharmacologic treatment literature for pediatric anxiety disorders, the design and methods of the CAMS trial are described.</p> <p>Results</p> <p>CAMS was a six-year, six-site, randomized controlled trial. Four hundred eighty-eight (N = 488) children and adolescents (ages 7-17 years) with DSM-IV-TR diagnoses of SAD, GAD, or SoP were randomly assigned to one of four treatment conditions: CBT, SRT, COMB, or PBO. Assessments of anxiety symptoms, safety, and functional outcomes, as well as putative mediators and moderators of treatment response were completed in a multi-measure, multi-informant fashion. Manual-based therapies, trained clinicians and independent evaluators were used to ensure treatment and assessment fidelity. A multi-layered administrative structure with representation from all sites facilitated cross-site coordination of the entire trial, study protocols and quality assurance.</p> <p>Conclusions</p> <p>CAMS offers a model for clinical trials methods applicable to psychosocial and psychopharmacological comparative treatment trials by using state-of-the-art methods and rigorous cross-site quality controls. CAMS also provided a large-scale examination of the relative and combined efficacy and safety of the best evidenced-based psychosocial (CBT) and pharmacologic (SSRI) treatments to date for the most commonly occurring pediatric anxiety disorders. Primary and secondary results of CAMS will hold important implications for informing practice-relevant decisions regarding the initial treatment of youth with anxiety disorders.</p> <p>Trial registration</p> <p>ClinicalTrials.gov NCT00052078.</p