756 research outputs found

    Bose-Einstein Condensation and strong-correlation behavior of phonons in ion traps

    Full text link
    We show that the dynamics of phonons in a set of trapped ions interacting with lasers is described by a Bose-Hubbard model whose parameters can be externally adjusted. We investigate the possibility of observing several quantum many-body phenomena, including (quasi) Bose-Einstein condensation as well as a superfluid-Mott insulator quantum phase transition.Comment: 5 pages, 3 figure

    DMRG and periodic boundary conditions: a quantum information perspective

    Get PDF
    We introduce a picture to analyze the density matrix renormalization group (DMRG) numerical method from a quantum information perspective. This leads us to introduce some modifications for problems with periodic boundary conditions in which the results are dramatically improved. The picture also explains some features of the method in terms of entanglement and teleportation.Comment: 4 page

    Root-associated fungal communities colonizing two dominant semiarid grasses: Hilaria sp. and Stipa sp.

    Get PDF
    We conducted a preliminary survey of the fungal communities associated with roots of Stipa hymenoides and Hilaria jamesii, two grasses native to the southwestern United States. Root samples from 10 different plants were collected at a semiarid grassland in Utah. Fungal communities were assessed using microscopic and molecular methods. Roots were cleared with KOH and stained using blue ink to visualize mycorrhizal and endophytic fungi. A total of 100 root segments were surface sterilized and plated on malt extract agar with antibiotics. Fungal endophytes were identified using nrITS primers.


Microscopic analyses showed that all root samples from both Hillaria and Stipa were colonized by dark septate and arbuscular mycorrhizal fungi. Vesicles and hyaline hyphae also were observed in all the roots. Sclerotia, a characteristic structure of some dark septate fungi were also found. Approximately 75 fungi were isolated representing at least 45 morphotypes. Molecular identification showed that both grasses are colonized by endophytes in the orders Pleosporales, Hypocreales, and Sordariales commonly found in semiarid grasses, liverworts, and mosses

    Simulating quantum-optical phenomena with cold atoms in optical lattices

    Get PDF
    We propose a scheme involving cold atoms trapped in optical lattices to observe different phenomena traditionally linked to quantum-optical systems. The basic idea consists of connecting the trapped atomic state to a non-trapped state through a Raman scheme. The coupling between these two types of atoms (trapped and free) turns out to be similar to that describing light-matter interaction within the rotating-wave approximation, the role of matter and photons being played by the trapped and free atoms, respectively. We explain in particular how to observe phenomena arising from the collective spontaneous emission of atomic and harmonic oscillator samples such as superradiance and directional emission. We also show how the same setup can simulate Bose-Hubbard Hamiltonians with extended hopping as well as Ising models with long-range interactions. We believe that this system can be realized with state of the art technology

    Innovaci贸n de la metodolog铆a docente en Farmacolog铆a a trav茅s del cine como recurso formativo.

    Get PDF
    Estudio interuniversitario del uso de las pel铆culas comerciales, como recurso educativo innovador, en la ense帽anza de la Farmacolog铆a de manera sistem谩tica en los alumnos de dicha asignatura de las universidades de C谩diz y M谩laga. Cabello MR, Medina I, Moreno R. Innovaci贸n de la metodolog铆a docente en Farmacolog铆a a trav茅s del cine como recurso formativo.FEMVol. 20 (S2) Suplemento 2, Octubre 2017 ISSN: 2014-9832Objetivo Analizar la adquisici贸n de competencias transversales, el grado de satisfacci贸n y motivaci贸n de los alumnos de Farmacolog铆a con la utilizaci贸n de las pel铆culas comerciales como recurso docente. MATERIAL Y METODOS Se realiz贸: 1- Preevaluaci贸n. Presentaci贸n y visualizaci贸n de la pel铆cula. 2- Resoluci贸n de las cuestiones planteadas con el trabajo personal y de grupo. 3- Debate. Realizaci贸n de un postest, encuesta de satisfacci贸n y valoraci贸n de la actividad por los estudiantes participantes. Valoraci贸n y an谩lisis de los cuestionarios y an谩lisis textual qualitativo de las observaciones de las encuestas de satisfacci贸n. Resultados En todas las cuestiones de satisfacci贸n de la actividad han considerado estar satisfechos/muy satisfechos el 70% de los estudiantes participantes. Confirmaci贸n de adquisici贸n de competencias transversales y espec铆ficas de farmacolog铆a. Conclusi贸n El recurso visual aumenta la motivaci贸n y el grado de satisfacci贸n de los estudiantes. Se facilita el debate y discusi贸n de puntos propuestos por el docente y los estudiantes, con un mayor aprovechamiento de la actividad. Consideramos una metodolog铆a muy 煤til y eficaz en el aprendizaje activo de los estudiantes.Universidad de M谩laga. Campus de Excelencia Internacional Andaluc铆a Tech