Modeling quasi-dark states with Temporal Coupled-Mode Theory

Coupled resonators are commonly used to achieve tailored spectral responses and allow novel functionalities in a broad range of applications, from optical modulation and filtering in integrated photonic circuits to the study of nonlinear dynamics in arrays of resonators. The Temporal Coupled-Mode Theory (TCMT) provides a simple and general tool that is widely used to model these devices and has proved to yield very good results in many different systems of low-loss, weakly coupled resonators. Relying on TCMT to model coupled resonators might however be misleading in some circumstances due to the lumped-element nature of the model. In this article, we report an important limitation of TCMT related to the prediction of dark states. Studying a coupled system composed of three microring resonators, we demonstrate that TCMT predicts the existence of a dark state that is in disagreement with experimental observations and with the more general results obtained with the Transfer Matrix Method (TMM) and the Finite-Difference Time-Domain (FDTD) simulations. We identify the limitation in the TCMT model to be related to the mechanism of excitation/decay of the supermodes and we propose a correction that effectively reconciles the model with expected results. A comparison with TMM and FDTD allows to verify both steady-state and transient solutions of the modified-TCMT model. The proposed correction is derived from general considerations, energy conservation and the non-resonant power circulating in the system, therefore it provides good insight on how the TCMT model should be modified to eventually account for the same limitation in a different coupled-resonator design. Moreover, our discussion based on coupled microring resonators can be useful for other electromagnetic resonant systems due to the generality and far-reach of the TCMT formalism.Comment: 7 pages, 4 figure

Spectral Engineering with Coupled Microcavities: Active Control of Resonant Mode-Splitting

Optical mode-splitting is an efficient tool to shape and fine-tune the spectral response of resonant nanophotonic devices. The active control of mode-splitting, however, is either small or accompanied by undesired resonance shifts, often much larger than the resonance-splitting. We report a control mechanism that enables reconfigurable and widely tunable mode-splitting while efficiently mitigating undesired resonance shifts. This is achieved by actively controlling the excitation of counter-traveling modes in coupled resonators. The transition from a large splitting (80 GHz) to a single-notch resonance is demonstrated using low power microheaters (35 mW). We show that the spurious resonance-shift in our device is only limited by thermal crosstalk and resonance-shift-free splitting control may be achieved.Comment: 4 pages, 3 figure

Reconfigurable silicon thermo-optical ring resonator switch based on Vernier effect control

A proof-of-concept for a new and entirely CMOS compatible thermo-optic reconfigurable switch based on a coupled ring resonator structure is experimentally demonstrated in this paper. Preliminary results show that a single optical device is capable of combining several functionalities, such as tunable filtering, non-blocking switching and reconfigurability, in a single device with compact footprint (~50μm x 30μm)

Anales de Edafología y Agrobiología Tomo 34 Número 3-4

Estudio de la materia orgánica del ranker atlántico. I. Caracterización general, por P. Rodríguez Seoane, T. Carballas y F. Guitián Ojea.-- Movimiento y distribución de sales solubles en suelos calizos, por F. G. Fernández, M. Caro y A. Cerda.-- The availability of added and native phosphorus to barley grown in sorne Egyptian soils .containing different levels of calciurn carbonate, by M. H. Nafady.-- The measurernent of soil pH in calciurn chloride solutions, by M. H. Nafady.- Nuevas aportaciones al conocimiento del género Mnema (nernatoda) y su distribución en los suelos españoles, por María Arias.-- Estudios bioquímicos y fisiológicos en aceituna. III. Variaciones en el crecimiento de hojas y frutos, por J. P. Donaire, A. J. Sánchez-Raya, J. López Corge y L. Recalde.-- Importancia de la rnicorrización espontánea en ensayos de nutrición vegetal en suelos deficientes en fósforo, por R. Azcón y J. M. Barea.-- Andosoles canarios. J. Características generales de estos suelos, por E. Fernández Caldas y M. L. Tejedor Salguero.-- Andosoles canarios. II. Intergrados andosol-tierra parda oligotrófica. Características morfológicas y quírnkas, por M. L. Tejedor Salguero y E. Fernández Caldas.-- Andosoles canarios. lll. Jntergrados andosol-tierra parda otigotrófica. Catacterísticas físicas, por E. Fernández Caldas y M. L. Tejedor Salguero.-- Andosoles canario;. IV. In ter grados andosol-tierra parda ohgotrófica. Características mineralógicas. Interpretación y clasificación, por C. Rodríguez Pascual, P. Quantin, M. L. Tejedor Salguero y E. Fernández Caldas.-- Estudios recapitualtivos.-- La vid una revisión de las condiciones del cultivo, por C. González O. y M. Lachica.—Notas científicas.-- Nota sobre la determinación del carbono orgánico en suelos, por J. F. Gallardo.—Notas.-- Ampliación de la Comisión Permanente de la Junta de Gobierno del Patronato Alonso de Herrera.-- Nombramiento de Secretario del Centro de Edafología y Biología Aplicada de Tenerife.-- Nombramientos en el Instituto de Alimentación v Productividad Animal.-- Cambio de representantes del Patronato Alonso de Herrera en la Comisión Asesora de la Investigación Científica y Técnica.-- Convenio con ASPA.-- Dimisión del Director del Centro de Edafología y Biología Aplicada del Segura de Murcia.-- Nombramientos de representantes en los C. R. l. D. A. S.-- Designación de Jurados para Premios del C. S. l. C.-- Informes del Secretario Adjunto del C. S. I. C. sobre reuniones en Europa.-- Convenio entre la Estación Experimental del Zaidín y la Universidad de Nápoles.-- Donación de terrenos a la Diputación de Badajoz.-- Seminario Oleícola Internacional.-- Congreso de la Unión Fitopatológica Mediterránea.-- Situaciones de personal.-- Reunión de la Comisión de Protección Vegetal.-- Día Forestal Mundial.-- Congresos y reuniones internacionales y viajes.-- Premio Agrícola Aedos.-- BibliografíaPeer reviewed2019-08.- CopyBook.- Libnova.- Biblioteca ICA

HTLV-1 infection in solid organ transplant donors and recipients in Spain

HTLV-1 infection is a neglected disease, despite infecting 10-15 million people worldwide and severe illnesses develop in 10% of carriers lifelong. Acknowledging a greater risk for developing HTLV-1 associated illnesses due to immunosuppression, screening is being widely considered in the transplantation setting. Herein, we report the experience with universal HTLV testing of donors and recipients of solid organ transplants in a survey conducted in Spain. All hospitals belonging to the Spanish HTLV network were invited to participate in the study. Briefly, HTLV antibody screening was performed retrospectively in all specimens collected from solid organ donors and recipients attended since the year 2008. A total of 5751 individuals were tested for HTLV antibodies at 8 sites. Donors represented 2312 (42.2%), of whom 17 (0.3%) were living kidney donors. The remaining 3439 (59.8%) were recipients. Spaniards represented nearly 80%. Overall, 9 individuals (0.16%) were initially reactive for HTLV antibodies. Six were donors and 3 were recipients. Using confirmatory tests, HTLV-1 could be confirmed in only two donors, one Spaniard and another from Colombia. Both kidneys of the Spaniard were inadvertently transplanted. Subacute myelopathy developed within 1 year in one recipient. The second recipient seroconverted for HTLV-1 but the kidney had to be removed soon due to rejection. Immunosuppression was stopped and 3 years later the patient remains in dialysis but otherwise asymptomatic. The rate of HTLV-1 is low but not negligible in donors/recipients of solid organ transplants in Spain. Universal HTLV screening should be recommended in all donor and recipients of solid organ transplantation in Spain. Evidence is overwhelming for very high virus transmission and increased risk along with the rapid development of subacute myelopathy

Recent results on heavy-ion induced reactions of interest for neutrinoless double beta decay at INFN-LNS

Abstract. The possibility to use a special class of heavy-ion induced direct reactions, such as double charge exchange reactions, is discussed in view of their application to extract information that may be helpful to determinate the nuclear matrix elements entering in the expression of neutrinoless double beta decay halflife. The methodology of the experimental campaign presently running at INFN - Laboratori Nazionali del Sud is reported and the experimental challenges characterizing such activity are describe

Anales de Edafología y Agrobiología Tomo 32 Número 9-10

Aportaciones para un mejor conocimiento de los suelos desarrollados sobre materiales calizos consolidados, por J. L. Moreno Alvarez y T. Badorrey Peracho.-- Estudio biológico y químico de Erica umbellata L., por M. Consolación Salas, Antonio Ballester y Ernesto Vieitez.--Contenido en metales de la nitrito reductasa del alga Chlorella, por J. Cárdenas, F. D. Pineda, F. F. de la Rosa, J. L. Barea y J. Rivas.-- Andosuelos de la provincia de Gerona. I. Estudio de sustancias minerales amorfas, por J. Rodríguez Sanchidrián y F Monturiol Rodríguez.-- Minerales de la arcilla en suelos de la provincia de Granada, por J. L. Martín Vivaldi, E. Galán Huertos y F. López Aguayo.-- Influence of foliar application of macro-nutrient on the plant growth and rnultiplication of viruses. I. Foliar application of nitrogen nutrient to tomato and its effect on host growth and potato virus X multiplication, by Rajendra Singh and Tej Pratap Mall.-- Heterodera Schachtii Schmidt, 1871 (Nematoda: Heteroderidae) en los suelos de las Islas Canarias, por A. Bello y Mª. D. Romero.-- Utiliización de una nueva fórmula de cálculo para la evaporación de Piché en regiones húmedas de España, por Jesús Seco, Angela Calvo y José Garmendía.-- Contribución al estudio de la técnica de Walkley y Black para la determinación de carbono orgánico de suelos, por Luisa Prat Pérez y Benito Sánchez.-- Estudio de la dinámica del crecimiento del limón en el sureste español, por O. Carpena, F. Romojaro, C. Alearaz y S. Llorente.-- Efecto de la aplicación de acetileno y ácido 2-cloroetilfosfónico sobre la fructificación y cosecha del olivo, por A. J. Sánchez-Raya, J. P. Donaire y L. Recalde.—Notas científicas.-- Estudio de fosfatasa ácida en plantas de A tropa belladona L. recogidas en otoño, por M. R. Felipe Antón y N. Velázquez Sánchez.—Notas.-- Nombramiento de Presidente del C. S. I. C.-- Constitución de la nueva Junta de Gobierno del Patronato Alonso de Herrera.-- Nombramiento de Consejeros de Número.-- Nombramiento de Consejeros Adjuntos.-- Designación del Comité Nacional de la Unión Internacional de Investigaciones sobre el Cuaternario.-- Rector de la Universidad de La Laguna.-- Distinción al Pro f. Zorita.-- European Grassland Federation (5th General Meeting).-- Reuniones nacionales.-- 1ª Reunión Nacional del Grupo de Trabajo del Cuaternario.-- Laboratorio de Micromorfología de Suelos.-- Próximo Congreso de Micromorfología.-- Reunión en La Mayora.-- BibliografíaPeer reviewed2019-08.- CopyBook.- Libnova.- Biblioteca ICA

New results from the NUMEN project

NUMEN aims at accessing experimentally driven information on Nuclear Matrix Elements (NME) involved in the half-life of the neutrinoless double beta decay (0νββ), by high-accuracy measurements of the cross sections of Heavy Ion (HI) induced Double Charge Exchange (DCE) reactions. First evidence about the possibility to get quantitative information about NME from experiments is found for the (18O,18Ne) and (20Ne,20O) reactions. Moreover, to infer the neutrino average masses from the possible measurement of the half-life of 0νββ decay, the knowledge of the NME is a crucial aspect. The key tools for this project are the high resolution Superconducting Cyclotron beams and the MAGNEX magnetic spectrometer at INFN Laboratori Nazionali del Sud in Catania (Italy). The measured cross sections are extremely low, limiting the present exploration to few selected isotopes of interest in the context of typically low-yield experimental runs. A major upgrade of the LNS facility is foreseen in order to increase the experimental yield of at least two orders of magnitude, thus making feasible a systematic study of all the cases of interest. peerReviewe