73,950 research outputs found

    Surface-wave solitons on the interface between a linear medium and a nonlocal nonlinear medium

    Full text link
    We address the properties of surface-wave solitons on the interface between a semi-infinite homogeneous linear medium and a semi-infinite homogeneous nonlinear nonlocal medium. The stability, energy flow and FWHM of the surface wave solitons can be affected by the degree of nonlocality of the nonlinear medium. We find that the refractive index difference affects the power distribution of the surface solitons in two media. We show that the different boundary values at the interface can lead to the different peak position of the surface solitons, but it can not influence the solitons stability with a certain degree of nonlocality.Comment: 8 pages, 14 figures, 15 references, and so o

    Anomalous Nernst and Hall effects in magnetized platinum and palladium

    Full text link
    We study the anomalous Nernst effect (ANE) and anomalous Hall effect (AHE) in proximity-induced ferromagnetic palladium and platinum which is widely used in spintronics, within the Berry phase formalism based on the relativistic band structure calculations. We find that both the anomalous Hall (ΟƒxyA\sigma_{xy}^A) and Nernst (Ξ±xyA\alpha_{xy}^A) conductivities can be related to the spin Hall conductivity (ΟƒxyS\sigma_{xy}^S) and band exchange-splitting (Ξ”ex\Delta_{ex}) by relations ΟƒxyA=Ξ”exeℏσxyS(EF)β€²\sigma_{xy}^A =\Delta_{ex}\frac{e}{\hbar}\sigma_{xy}^S(E_F)' and Ξ±xyA=βˆ’Ο€23kB2TΞ”exℏσxys(ΞΌ)"\alpha_{xy}^A = -\frac{\pi^2}{3}\frac{k_B^2T\Delta_{ex}}{\hbar}\sigma_{xy}^s(\mu)", respectively. In particular, these relations would predict that the ΟƒxyA\sigma_{xy}^A in the magnetized Pt (Pd) would be positive (negative) since the ΟƒxyS(EF)β€²\sigma_{xy}^S(E_F)' is positive (negative). Furthermore, both ΟƒxyA\sigma_{xy}^A and Ξ±xyA\alpha_{xy}^A are approximately proportional to the induced spin magnetic moment (msm_s) because the Ξ”ex\Delta_{ex} is a linear function of msm_s. Using the reported msm_s in the magnetized Pt and Pd, we predict that the intrinsic anomalous Nernst conductivity (ANC) in the magnetic platinum and palladium would be gigantic, being up to ten times larger than, e.g., iron, while the intrinsic anomalous Hall conductivity (AHC) would also be significant.Comment: Accepted for publication in the Physical Review

    Information filtering via biased heat conduction

    Full text link
    Heat conduction process has recently found its application in personalized recommendation [T. Zhou \emph{et al.}, PNAS 107, 4511 (2010)], which is of high diversity but low accuracy. By decreasing the temperatures of small-degree objects, we present an improved algorithm, called biased heat conduction (BHC), which could simultaneously enhance the accuracy and diversity. Extensive experimental analyses demonstrate that the accuracy on MovieLens, Netflix and Delicious datasets could be improved by 43.5%, 55.4% and 19.2% compared with the standard heat conduction algorithm, and the diversity is also increased or approximately unchanged. Further statistical analyses suggest that the present algorithm could simultaneously identify users' mainstream and special tastes, resulting in better performance than the standard heat conduction algorithm. This work provides a creditable way for highly efficient information filtering.Comment: 4 pages, 3 figure
    • …
    corecore