1,686 research outputs found

    Switchable ultrastrong coupling in circuit QED

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    Superconducting quantum circuits possess the ingredients for quantum information processing and for developing on-chip microwave quantum optics. From the initial manipulation of few-level superconducting systems (qubits) to their strong coupling to microwave resonators, the time has come to consider the generation and characterization of propagating quantum microwaves. In this paper, we design a key ingredient that will prove essential in the general frame: a swtichable coupling between qubit(s) and transmission line(s) that can work in the ultrastrong coupling regime, where the coupling strength approaches the qubit transition frequency. We propose several setups where two or more loops of Josephson junctions are directly connected to a closed (cavity) or open transmission line. We demonstrate that the circuit induces a coupling that can be modulated in strength and type. Given recent studies showing the accessibility to the ultrastrong regime, we expect our ideas to have an immediate impact in ongoing experiments

    Quality and Safety of Meat Products

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    The Rome Declaration onWorld Food Security includes the right of everyone to have access to Thus, this increase in population poses great food challenges in general, and to the meat industry in and the distribution of food and some of the changes will bring potential problems to food safety and be in developing countries. It is well known that development stimulates an increase in the demand certification. Scientists have much to contribute to this new scenario. Our role will be critical to ensure food. Food quality is a complex term that includes, in addition to safety, other intrinsic characteristics, for high-quality protein, and among candidates, food undoubtedly includes meat and meat products. future population health, nutrition and sensory-acceptable foods. human suffering and with respect to economic costs. Scientific advances have allowed to better know nutritional quality. Food-borne diseases are a major problem around the world, both in regards to of consumers are much more conscious with respect to what they eat, and their demands for quality particular. To meet the needs of these populations, we will have to reorganize production systems quality. In 2020, the world’s population will surpass 7.5 billion of people and the main increases will safe and nutritious food, and the World Summit on Food recognized the link between food safety and such as appearance, color, texture and flavor and also extrinsic characteristics, such as labelling or the nutritional characteristics of foods and their effects on health. This means that a large proportion..

    Quality and Safety of Meat Products

    Get PDF
    Food safety is a major problem around the world, both regarding human suffering and with respect to economic costs. Scientific advances have increased our knowledge surrounding the nutritional characteristics of foods and their effects on health. This means that a large proportion of consumers are much more conscious with respect to what they eat and their demands for quality food. Food quality is a complex term that includes, in addition to safety, other intrinsic characteristics, such as appearance, color, texture and flavor, and also extrinsic characteristics, such as perception or involvement

    Resonant nonlinearity management for nonlinear-Schr\"{o}dinger solitons

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    We consider effects of a periodic modulation of the nonlinearity coefficient on fundamental and higher-order solitons in the one-dimensional NLS equation, which is an issue of direct interest to Bose-Einstein condensates in the context of the Feshbach-resonance control, and fiber-optic telecommunications as concerns periodic compensation of the nonlinearity. We find from simulations, and explain by means of a straightforward analysis, that the response of a fundamental soliton to the weak perturbation is resonant, if the modulation frequency ω\omega is close to the intrinsic frequency of the soliton. For higher-order nn-solitons with n=2n=2 and 3, the response to an extremely weak perturbation is also resonant, if ω\omega is close to the corresponding intrinsic frequency. More importantly, a slightly stronger drive splits the 2- or 3-soliton, respectively, into a set of two or three moving fundamental solitons. The dependence of the threshold perturbation amplitude, necessary for the splitting, on ω\omega has a resonant character too. Amplitudes and velocities of the emerging fundamental solitons are accurately predicted, using exact and approximate conservation laws of the perturbed NLS equation.Comment: 14 pages, 6 figure

    Klein tunneling and Dirac potentials in trapped ions

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    We propose the quantum simulation of the Dirac equation with potentials, allowing the study of relativistic scaterring and the Klein tunneling. This quantum relativistic effect permits a positive-energy Dirac particle to propagate through a repulsive potential via the population transfer to negative-energy components. We show how to engineer scalar, pseudoscalar, and other potentials in the 1+1 Dirac equation by manipulating two trapped ions. The Dirac spinor is represented by the internal states of one ion, while its position and momentum are described by those of a collective motional mode. The second ion is used to build the desired potentials with high spatial resolution.Comment: 4 pages, 3 figures, minor change

    Scattering of coherent states on a single artificial atom

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    In this work we theoretically analyze a circuit QED design where propagating quantum microwaves interact with a single artificial atom, a single Cooper pair box. In particular, we derive a master equation in the so-called transmon regime, including coherent drives. Inspired by recent experiments, we then apply the master equation to describe the dynamics in both a two-level and a three-level approximation of the atom. In the two-level case, we also discuss how to measure photon antibunching in the reflected field and how it is affected by finite temperature and finite detection bandwidth.Comment: 18 pages, 7 figure

    On the Asymptotic Dirichlet Problem for the Minimal Hypersurface Equation in a Hadamard Manifold

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    We study the Dirichlet problem at infinity on a Cartan-Hadamard manifold M of dimension n 2 for a large class of operators containing, in particular, the p-Laplacian and the minimal graph operator. We extend several existence results obtained for the p-Laplacian to our class of operators. As an application of our main result, we prove the solvability of the asymptotic Dirichlet problem for the minimal graph equation for any continuous boundary data on a (possibly non rotationally symmetric) manifold whose sectional curvatures are allowed to decay to 0 quadratically.Peer reviewe

    Asymptotic Plateau problem for prescribed mean curvature hypersurfaces

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    We prove the existence of solutions to the asymptotic Plateau problem for hypersurfaces of prescribed mean curvature in Cartan-Hadamard manifolds N. More precisely, given a suitable subset L of the asymptotic boundary of N and a suitable function H on N, we are able to construct a set of locally finite perimeter whose boundary has generalized mean curvature H provided that N satisfies the so-called strict convexity condition and that its sectional curvatures are bounded from above by a negative constant. We also obtain a multiplicity result in low dimensions.Peer reviewe

    Unleashing Optics and Optoacoustics for Developmental Biology

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    The past decade marked an optical revolution in biology: an unprecedented number of optical techniques were developed and adopted for biological exploration, demonstrating increasing interest in optical imaging and in vivo interrogations. Optical methods have become faster and have reached nanoscale resolution, and are now complemented by optoacoustic (photoacoustic) methods capable of imaging whole specimens in vivo. Never before were so many optical imaging barriers broken in such a short time-frame: with new approaches to optical microscopy and mesoscopy came an increased ability to image biology at unprecedented speed, resolution, and depth. This review covers the most relevant techniques for imaging in developmental biology, and offers an outlook on the next steps for these technologies and their applications.The work on this review article has received funding from the Deutsche Forschungsgemeinschaft (DFG), Germany (Leibniz Prize 2013; NT 3/10 1) and the Federal Ministry of Education and Research (BMBF), Photonic Science Germany, Tech2See 13N12623/ 4. J.R. acknowledges support from the European Commission FP7 CIG grant HIGH THROUGH PUT TOMO, and Spanish MINECO grant MESO IMAGING FIS2013 41802 R
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