184 research outputs found

    Approximate transformations of bipartite pure-state entanglement from the majorization lattice

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    We study the problem of deterministic transformations of an \textit{initial} pure entangled quantum state, ψ|\psi\rangle, into a \textit{target} pure entangled quantum state, ϕ|\phi\rangle, by using \textit{local operations and classical communication} (LOCC). A celebrated result of Nielsen [Phys. Rev. Lett. \textbf{83}, 436 (1999)] gives the necessary and sufficient condition that makes this entanglement transformation process possible. Indeed, this process can be achieved if and only if the majorization relation ψϕ\psi \prec \phi holds, where ψ\psi and ϕ\phi are probability vectors obtained by taking the squares of the Schmidt coefficients of the initial and target states, respectively. In general, this condition is not fulfilled. However, one can look for an \textit{approximate} entanglement transformation. Vidal \textit{et. al} [Phys. Rev. A \textbf{62}, 012304 (2000)] have proposed a deterministic transformation using LOCC in order to obtain a target state χopt|\chi^\mathrm{opt}\rangle most approximate to ϕ|\phi\rangle in terms of maximal fidelity between them. Here, we show a strategy to deal with approximate entanglement transformations based on the properties of the \textit{majorization lattice}. More precisely, we propose as approximate target state one whose Schmidt coefficients are given by the supremum between ψ\psi and ϕ\phi. Our proposal is inspired on the observation that fidelity does not respect the majorization relation in general. Remarkably enough, we find that for some particular interesting cases, like two-qubit pure states or the entanglement concentration protocol, both proposals are coincident.Comment: Revised manuscript close to the accepted version in Physica A (10 pages, 1 figure

    Multi-class classification based on quantum state discrimination

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    We present a general framework for the problem of multi-class classification using classification functions that can be interpreted as fuzzy sets. We specialize these functions in the domain of Quantum-inspired classifiers, which are based on quantum state discrimination techniques. In particular, we use unsharp observables (Positive Operator-Valued Measures) that are determined by the training set of a given dataset to construct these classification functions. We show that such classifiers can be tested on near-term quantum computers once these classification functions are “distilled” (on a classical platform) from the quantum encoding of a training dataset. We compare these experimental results with their theoretical counterparts and we pose some questions for future research

    On the lattice structure of probability spaces in quantum mechanics

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    Let C be the set of all possible quantum states. We study the convex subsets of C with attention focused on the lattice theoretical structure of these convex subsets and, as a result, find a framework capable of unifying several aspects of quantum mechanics, including entanglement and Jaynes' Max-Ent principle. We also encounter links with entanglement witnesses, which leads to a new separability criteria expressed in lattice language. We also provide an extension of a separability criteria based on convex polytopes to the infinite dimensional case and show that it reveals interesting facets concerning the geometrical structure of the convex subsets. It is seen that the above mentioned framework is also capable of generalization to any statistical theory via the so-called convex operational models' approach. In particular, we show how to extend the geometrical structure underlying entanglement to any statistical model, an extension which may be useful for studying correlations in different generalizations of quantum mechanics.Comment: arXiv admin note: substantial text overlap with arXiv:1008.416

    Optimal common resource in majorization-based resource theories

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    We address the problem of finding the optimal common resource for an arbitrary family of target states in quantum resource theories based on majorization, that is, theories whose conversion law between resources is determined by a majorization relationship, such as it happens with entanglement, coherence or purity. We provide a conclusive answer to this problem by appealing to the completeness property of the majorization lattice. We give a proof of this property that relies heavily on the more geometric construction provided by the Lorenz curves, which allows to explicitly obtain the corresponding infimum and supremum. Our framework includes the case of possibly non-denumerable sets of target states (i.e. targets sets described by continuous parameters). In addition, we show that a notion of approximate majorization, which has recently found application in quantum thermodynamics, is in close relation with the completeness of this lattice. Finally, we provide some examples of optimal common resources within the resource theory of quantum coherence.Fil: Bosyk, Gustavo Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; ArgentinaFil: Bellomo, Guido. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Investigación en Ciencias de la Computación. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Investigación en Ciencias de la Computación; ArgentinaFil: Holik, Federico Hernán. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; ArgentinaFil: Freytes, H.. Università Degli Studi Di Cagliari.; ItaliaFil: Sergioli, Giuseppe. Università Degli Studi Di Cagliari.; Itali

    PKM UD MITRA JAMUR DALAM UPAYA PENINGKATAN PENJUALAN PRODUK JAMUR TIRAM MENGGUNAKAN E-COMMERCE

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    Mahalnya proses marketing secara manual, menjadikan penawaran penjualan secara online menjadi pilihan alternatif. Metode yang dilakukan dalam pelaksanaan PKM ini adalah dimulai dari menganalisis kebutuhan, dimana pelayanan, batasan, dan sosialisasi. Tujuan sistem ditentukan melalui observasi dan wawancara dengan pemilik UD Mitra Jamur. Pada perancangan desain sistem, website dirancang dengan program CMS Opencart. Kemudian dilanjutkan tahap implementasi dan diujicobakan. Pada tahapan uji coba, e-commerce diintegrasikan dan diuji sebagai sistem yang lengkap untuk menjamin bahwa persyaratan sistem telah dipenuhi

    On the connection between Complementarity and Uncertainty Principles in the Mach-Zehnder interferometric setting

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    We revisit, in the framework of Mach-Zehnder interferometry, the connection between the complementarity and uncertainty principles of quantum mechanics. Specifically, we show that, for a pair of suitably chosen observables, the trade-off relation between the complementary path information and fringe visibility is equivalent to the uncertainty relation given by Schr\"odinger and Robertson, and to the one provided by Landau and Pollak as well. We also employ entropic uncertainty relations (based on R\'enyi entropic measures) and study their meaning for different values of the entropic parameter. We show that these different values define regimes which yield qualitatively different information concerning the system, in agreement with findings of [A. Luis, Phys. Rev. A 84, 034101 (2011)]. We find that there exists a regime for which the entropic uncertinty relations can be used as criteria to pinpoint non trivial states of minimum uncertainty.Comment: 7 pages, 2 figure

    Short Fiber Reinforced Thermoplastics: Prediction of Stiffness in Injection Molded PS-PPO Blends

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    The prediction of stiffness in short fiber reinforced thermoplastics is stud ied as a function of fiber length using injection molded blends of PS and PPO. The theoret ical models for predicting composite stiffness are reviewed. The results are first compared with the theoretical models advanced for uniaxially aligned composites. These models predict higher than experimental values. However, agreement between the predictions and experimental values improves when the effect of fiber orientation distribution in the injec tion molded samples is taken into account and as the ductility (or the PPO content) of the matrix increases. Cox's model when used with the "laminate analogy" gives the closest prediction to the experimental stiffness. Reinforcement efficiency factor for stiffness is a strong function of retained fiber lengths. The dependence of composite stiffness on the matrix ductility and the effects of compatibility on the mechanical properties of PS-PPO blend system are also discussed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68613/2/10.1177_089270579100400205.pd

    Material Cycles and Chemicals: Dynamic Material Flow Analysis of Contaminants in Paper Recycling

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    This study provides a systematic approach for assessment of contaminants in materials for recycling. Paper recycling is used as an illustrative example. Three selected chemicals, bisphenol A (BPA), diethylhexyl phthalate (DEHP) and mineral oil hydrocarbons (MOHs), are evaluated within the paper cycle. The approach combines static material flow analysis (MFA) with dynamic material and substance flow modeling. The results indicate that phasing out of chemicals is the most effective measure for reducing chemical contamination. However, this scenario was also associated with a considerable lag phase (between approximately one and three decades) before the presence of chemicals in paper products could be considered insignificant. While improved decontamination may appear to be an effective way of minimizing chemicals in products, this may also result in lower production yields. Optimized waste material source-segregation and collection was the least effective strategy for reducing chemical contamination, if the overall recycling rates should be maintained at the current level (approximately 70% for Europe). The study provides a consistent approach for evaluating contaminant levels in material cycles. The results clearly indicate that mass-based recycling targets are not sufficient to ensure high quality material recycling
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