826 research outputs found

    Digital Quantum Simulation with Rydberg Atoms

    Full text link
    We discuss in detail the implementation of an open-system quantum simulator with Rydberg states of neutral atoms held in an optical lattice. Our scheme allows one to realize both coherent as well as dissipative dynamics of complex spin models involving many-body interactions and constraints. The central building block of the simulation scheme is constituted by a mesoscopic Rydberg gate that permits the entanglement of several atoms in an efficient, robust and quick protocol. In addition, optical pumping on ancillary atoms provides the dissipative ingredient for engineering the coupling between the system and a tailored environment. As an illustration, we discuss how the simulator enables the simulation of coherent evolution of quantum spin models such as the two-dimensional Heisenberg model and Kitaev's toric code, which involves four-body spin interactions. We moreover show that in principle also the simulation of lattice fermions can be achieved. As an example for controlled dissipative dynamics, we discuss ground state cooling of frustration-free spin Hamiltonians.Comment: submitted to special issue "Quantum Information with Neutral Particles" of "Quantum Information Processing

    EROSÃO EM ÁREA RURAL NO MUNICÍPIO DE NOVA VENEZA (GO): ASPECTOS GEOMORFOLÓGICOS DA FAZENDA VARJÃO

    Get PDF
    A área de estudo está localizada na área rural do município de Nova Veneza (GO), onde a fazenda Varjão é pioneira na produção agrícola e na criação de gado. Esse estudo identificou os aspectos geomorfológicos da área em questão, tais aspectos demonstram uma suscetibilidade natural da área à processos erosivos, essa situação foi potencializada pela ação antrópica. A cobertura original foi retirada e em seu lugar implantaram pastagens e agricultura, favorecendo a ação da erosão

    Forest Biodiversity Assessment in Peruvian Andean Montane Cloud Forest

    Get PDF
    Cloud forests are unusual and fragile habitats, being one of the least studied and least understood ecosystems. The tropical Andean dominion is considered one of the most significant places in the world as rega rds biological diversity, with a very high level of endemism. The biodiversity was analysed in an isolated remnant area of a tropical montane cloud forest known as the ?Bosque de Neblina de Cuyas?, in the North of the Peruvian Andean range. Composition, structure and dead wood were measured or estimated. The values obtained were compared with other cloud forests. The study revealed a high level of forest biodiversity, although the level of biodiversity differs from one area to another: in the inner areas, where human pressure is almost inexistent, the biodiversity values increase. The high species richness and the low dominance among species bear testimony to this montane cloud forest as a real enclave of biodiversity

    Measurement of the cross section for isolated-photon plus jet production in pp collisions at √s=13 TeV using the ATLAS detector

    Get PDF
    The dynamics of isolated-photon production in association with a jet in proton–proton collisions at a centre-of-mass energy of 13 TeV are studied with the ATLAS detector at the LHC using a dataset with an integrated luminosity of 3.2 fb−1. Photons are required to have transverse energies above 125 GeV. Jets are identified using the anti- algorithm with radius parameter and required to have transverse momenta above 100 GeV. Measurements of isolated-photon plus jet cross sections are presented as functions of the leading-photon transverse energy, the leading-jet transverse momentum, the azimuthal angular separation between the photon and the jet, the photon–jet invariant mass and the scattering angle in the photon–jet centre-of-mass system. Tree-level plus parton-shower predictions from Sherpa and Pythia as well as next-to-leading-order QCD predictions from Jetphox and Sherpa are compared to the measurements

    Sistema de Simulação de Alagamentos: SIGMAOn

    Get PDF
    SIGMAOn é um sistema de Informação Geográfica que oferece recursos de simulação de alagamentos com visualização de pontos e áreas alagadas, bem como rotas em cenários de inundação. Este artigo apresenta uma extensão do SIGMAOn para oferecer visualização de impacto de um alagamento por meio de fotos, sob uma perspectiva de visão em primeira pessoa. O trabalho também tem como objetivos o levantamento de fotos de locais alagáveis, definição de técnicas para extração de metragem e desenho dealagamentos sobre fotos. Foram aplicados conceitos de geometria para projeção de ruas alagadas sobre fotos de locais alagáveis. O trabalho oferece uma forma de visualização sob a perspectiva do solo. O trabalho traz uma extensão móvel e seus recursos. Uma análisecomparativa entre os Sistemas de Informações Geograficas (SIG) já existentes. Além disso, foram definidas as técnicas de extração de metragem e projeção de alagamentos

    A search for resonances decaying into a Higgs boson and a new particle X in the XH → qqbb final state with the ATLAS detector

    Get PDF
    A search for heavy resonances decaying into a Higgs boson (H) and a new particle (X) is reported, utilizing 36.1 fb−1 of proton–proton collision data at collected during 2015 and 2016 with the ATLAS detector at the CERN Large Hadron Collider. The particle X is assumed to decay to a pair of light quarks, and the fully hadronic final state is analysed. The search considers the regime of high XH resonance masses, where the X and H bosons are both highly Lorentz-boosted and are each reconstructed using a single jet with large radius parameter. A two-dimensional phase space of XH mass versus X mass is scanned for evidence of a signal, over a range of XH resonance mass values between 1 TeV and 4 TeV, and for X particles with masses from 50 GeV to 1000 GeV. All search results are consistent with the expectations for the background due to Standard Model processes, and 95% CL upper limits are set, as a function of XH and X masses, on the production cross-section of the resonance
    corecore