20,698 research outputs found

    Tunable Quantum Hall Edge Conduction in Bilayer Graphene through Spin-Orbit Interaction

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    Bilayer graphene, in the presence of a one-sided spin-orbit interaction (SOI) induced by a suitably chosen substrate, is predicted to exhibit unconventional Quantum Hall states. The new states arise due to strong SOI-induced splittings of the eight zeroth Landau levels, which are strongly layer-polarized, residing fully or partially on one of the two graphene layers. In particular, an Ising SOI in the meV scale is sufficient to invert the Landau level order between the n=0n=0 and n=1n=1 orbital levels under moderately weak magnetic fields B≲10B \lesssim 10\~T. Furthermore, when the Ising field opposes the BB field, the order of the spin-polarized levels can also be inverted. We show that, under these conditions, three different compensated electron-hole phases, with equal concentrations of electrons and holes, can occur at Ξ½=0\nu = 0 filling. The three phases have distinct edge conductivity values. One of the phases is especially interesting, since its edge conduction can be turned on and off by switching the sign of the interlayer bias.Comment: 10 pages, 5 figure

    Zc(3900)/Zc(3885)Z_c(3900)/Z_c(3885) as a virtual state from Ο€J/Οˆβˆ’DΛ‰βˆ—D\pi J/\psi-\bar{D}^*D interaction

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    In this work, we study the J/ΟˆΟ€J/\psi\pi and DΛ‰βˆ—D\bar{D}^*D invariant mass spectra of the Y(4260)Y(4260) decay to find out the origin of the Zc(3900)Z_c(3900) and Zc(3885)Z_c(3885) structures. The J/ΟˆΟ€βˆ’DΛ‰βˆ—DJ/\psi \pi-\bar{D}^{*}D interaction is studied in a coupled-channel quasipotential Bethe-Saltpeter equation approach, and embedded to the Y(4260)Y(4260) decay process to reproduce both J/ΟˆΟ€βˆ’J/\psi\pi^- and Dβˆ—βˆ’D0D^{*-}D^0 invariant mass spectra observed at BESIII simultaneously. It is found out that a virtual state at energy about 3870 MeV is produced from the interaction when both invariant mass spectra are comparable with the experiment. The results support that both Zc(3900)Z_c(3900) and Zc(3885)Z_c(3885) have the same origin, that is, a virtual state from J/ΟˆΟ€βˆ’DΛ‰βˆ—DJ/\psi \pi-\bar{D}^*{D} interaction, in which the DΛ‰βˆ—D\bar{D}^*{D} interaction is more important and the coupling between DΛ‰βˆ—D\bar{D}^*{D} and J/ΟˆΟ€J/\psi\pi channels plays a minor role.Comment: 8 pages, 4 figures, more reference adde

    Interface dynamics under nonequilibrium conditions: from a self-propelled droplet to dynamic pattern evolution

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    In this article, we describe the instability of a contact line under nonequilibrium conditions mainly based on the results of our recent studies. Two experimental examples are presented: the self-propelled motion of a liquid droplet and spontaneous dynamic pattern formation. For the self-propelled motion of a droplet, we introduce an experiment in which a droplet of aniline sitting on an aqueous layer moves spontaneously at an air-water interface. The spontaneous symmetry breaking of Marangoni-driven spreading causes regular motion. In a circular Petri dish, the droplet exhibits either beeline motion or circular motion. On the other hand, we show the emergence of a dynamic labyrinthine pattern caused by dewetting of a metastable thin film from the air-water interface. The contact line between the organic phase and aqueous phase forms a unique spatio-temporal pattern characterized as a dynamic labyrinthine. Motion of the contact line is controlled by diffusion processes. We propose a theoretical model to interpret essential aspects of the observed dynamic behavior
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