27,480 research outputs found

    Spin-orbit mode transfer via a classical analog of quantum teleportation

    Full text link
    We translate the quantum teleportation protocol into a sequence of coherent operations involving three degrees of freedom of a classical laser beam. The protocol, which we demonstrate experimentally, transfers the polarisation state of the input beam to the transverse mode of the output beam. The role of quantum entanglement is played by a non-separable mode describing the path and transverse degrees of freedom. Our protocol illustrates the possibility of new optical applications based on this intriguing classical analogue of quantum entanglement.Comment: 5 pages, 7 figure

    Perturbed Self-Similar Massless Scalar Field in the Spacetimes with Circular Symmetry in 2+1 Gravity

    Full text link
    We present in this work the study of the linear perturbations of the 2+1-dimensional circularly symmetric solution, obtained in a previous work, with kinematic self-similarity of the second kind. We have obtained an exact solution for the perturbation equations and the possible perturbation modes. We have shown that the background solution is a stable solution.Comment: no figure

    On the Levi-Civita solutions with cosmological constant

    Full text link
    The main properties of the Levi-Civita solutions with the cosmological constant are studied. In particular, it is found that some of the solutions need to be extended beyond certain hypersurfaces in order to have geodesically complete spacetimes. Some extensions are considered and found to give rise to black hole structure but with plane symmetry. All the spacetimes that are not geodesically complete are Petrov type D, while in general the spacetimes are Petrov type I.Comment: Typed in Revtex, including two figures. To appear in Phys. Rev.

    Effectiveness reduction of nucleopolyhedrovirus against Chrysodeixis includens days after application in soybean plants.

    Get PDF
    Made available in DSpace on 2019-12-02T18:13:58Z (GMT). No. of bitstreams: 1 36925.pdf: 230755 bytes, checksum: 66fbafb44173471ea6429fa4170efd9c (MD5) Previous issue date: 2018bitstream/item/205916/1/36925.pd

    Gyroscope precession in cylindrically symmetric spacetimes

    Get PDF
    We present calculations of gyroscope precession in spacetimes described by Levi-Civita and Lewis metrics, under different circumstances. By doing so we are able to establish a link between the parameters of the metrics and observable quantities, providing thereby a physical interpretation for those parameters, without specifying the source of the field.Comment: 13 pages, Latex. To appear in Class.Q.Gra

    Astigmatic tomography of orbital angular momentum superpositions

    Full text link
    We use astigmatic transformations to characterize two-dimensional superpositions of Orbital Angular Momentum (OAM) states in laser beams. We propose two methods for doing this, both relying only on astigmatic transformations, viewed as rotations on the Poincar\'e sphere, followed by imaging. These methods can be used as a tomographic tool for communication protocols based on optical vortices.Comment: Submitted to Physical Rivew

    Surface superconductivity in multilayered rhombohedral graphene: Supercurrent

    Full text link
    The supercurrent for the surface superconductivity of a flat-band multilayered rhombohedral graphene is calculated. Despite the absence of dispersion of the excitation spectrum, the supercurrent is finite. The critical current is proportional to the zero-temperature superconducting gap, i.e., to the superconducting critical temperature and to the size of the flat band in the momentum space
    corecore