3,980 research outputs found

    Brick tilings—new insights

    Get PDF

    Steady state current transfer and scattering theory

    Full text link
    The correspondence between the steady state theory of current transfer and scattering theory in a system of coupled tight-binding models of 1-dimensional wires is explored. For weak interwire coupling both calculations give nearly identical results, except at singular points associated with band edges. The effect of decoherence in each of these models is studied using a generalization of the Liouville-von Neuman equation suitable for steady-state situations. An example of a single impurity model is studied in details, leading to a lattice model of scattering off target that affects both potential scattering and decoherence. For an impurity level lying inside the energy band, the transmission coefficient diminishes with increasing dephasing rate, while the opposite holds for impurity energy outside the band. The efficiency of current transfer in the coupled wire system decreases with increasing dephasing.Comment: 22 pages, 13 figure

    Steady state theory of current transfer

    Full text link
    Current transfer is defined as a charge transfer process where the transferred charge carries information about its original motion. We have recently suggested that such transfer causes the asymmetry observed in electron transfer induced by circularly polarized light through helical wires. This paper presents the steady state theory of current transfer within a tight binding model of coupled wires systems. The efficiency of current transfer is quantified in terms of the calculated asymmetry in the system response to a steady current imposed on one of the wires, with respect to the imposed current direction.Comment: 25 pages, 14 figure

    Anisotropic thermal magnetoresistance for an active control of radiative heat transfer

    Full text link
    We predict a huge anisotropic thermal magnetoresistance (ATMR) in the near-field radiative heat transfer between magneto-optical particles when the direction of an external magnetic field is changed with respect to the heat current direction. We illustrate this effect with the case of two InSb spherical particles where we find that the ATMR amplitude can reach values of up to 800% for a magnetic field of 5 T, which is many orders of magnitude larger than its spintronic analogue in electronic devices. This thermomagnetic effect could find broad applications in the fields of ultrafast thermal management as well as magnetic and thermal remote sensing.Comment: 6 pages, 4 figure

    In-Network Retransmissions in Named Data Networking

    Get PDF
    The strategy layer is an important architectural component in both Content-Centric Networking (CCN) and Named Data Networking (NDN). This component introduces a new forwarding model that allows an application to configure its namespace with a forwarding strategy. A core mechanism in every forwarding strategy is the decision of whether to retransmit an unsatisfied Interest or to wait for an application retransmission. While some applications request control of all retransmissions, others rely on the assumption that the strategy will retransmit an Interest when it is not satisfied. Although an application can select the forwarding strategy used in the local host, it cannot guarantee the selection of the same strategy in other nodes in the network, especially in shared resource environments. In some scenarios, a developer must bind the implementation of the application to the details of the deployed forwarding strategy to guarantee the correctness of his application. In this paper we discuss the core mechanisms of a forwarding strategy in NDN, and we explore the importance and impact of in-network retransmissions on the application\u27s performance and correctness. We propose and implement a simple forwarding strategy abstraction that allows the application to decide whether a network retransmission is required, and differentiate application retransmissions from network retransmissions. We show that in some scenarios, such as multiple producers application or multipath consumer-producer service, the proposed abstraction can significantly reduce the percentage of unsatisfied Interests
    • …
    corecore