Topological confinement in graphene bilayer quantum rings

We demonstrate the existence of localized electron and hole states in a ring-shaped potential kink in biased bilayer graphene. Within the continuum description, we show that for sharp potential steps the Dirac equation describing carrier states close to the K (or K') point of the first Brillouin zone can be solved analytically for a circular kink/anti-kink dot. The solutions exhibit interfacial states which exhibit Aharonov-Bohm oscillations as functions of the height of the potential step and/or the radius of the ring

Heterosis and its components in crosses among high quality protein maize populations.

The objetive of the present study was to investigate heterosis in high quality protein maize populations of distinct grain type groups. Agronomic traits and reaction to some leaf diseases of 19 yellow grain populations were assessed in a partial diallel grown in four environments. For grain yield trait, only variety effects and average heterosis were significant, indicating that the best intervarietal hybrids can be predicted using the means of the parental populations. The BR 473 and CMS 52 flint populations, the CMS 474 and ZQP 103 dent populations are recommended for an inter-group reciprocal recurrent selection program. In a decreasing order of preference, the dent type CMS 474, ZQP 103 and ZQP 101 populations and the flint type BR 473, CMS 455C, CMS 453, CMS 52, CMS 455 and CMS 458 are recommended to form composites

Microfenótipos e proteínas associados à expressão da resistência durável à ferrugem da folha do trigo.

Editores técnicos: Joseani Mesquita Antunes, Ana Lídia Variani Bonato, Márcia Barrocas Moreira Pimentel

Time Resolution and Linearity Measurements for a Scintillating Fiber Detector Instrumented with VLPC's

The time resolution for a charged particle detection is reported for a typical scintillating fiber detector instrumented with Rockwell HISTE-IV Visible Light Photon Counters. The resolution measurements are shown to agree with a simple Monte Carlo model, and the model is used to make recomendations for improved performance. In addition, the gain linearity of a sample of VLPC devices was measured. The gain is shown to be linear for incident light intensities which produce up to approximately 600 photoelectrons per event.Comment: 18 pages, 14 figures; Submitted to Nucl. Instr & Meth. in Phys. Res. A; Please direct correspondence to [email protected]

Conditions for non-monotonic vortex interaction in two-band superconductors

We describe a semi-analytic approach to the two-band Ginzburg-Landau theory, which predicts the behavior of vortices in two-band superconductors. We show that the character of the short-range vortex-vortex interaction is determined by the sign of the normal domain - superconductor interface energy, in analogy with the conventional differentiation between type-I and type-II superconductors. However, we also show that the long-range interaction is determined by a modified Ginzburg-Landau parameter $\kappa^*$, different from the standard $\kappa$ of a bulk superconductor. This opens the possibility for non-monotonic vortex-vortex interaction, which is temperature-dependent, and can be further tuned by alterations of the material on the microscopic scale

Multipartite quantum nonlocality under local decoherence

We study the nonlocal properties of two-qubit maximally-entangled and N-qubit Greenberger-Horne-Zeilinger states under local decoherence. We show that the (non)resilience of entanglement under local depolarization or dephasing is not necessarily equivalent to the (non)resilience of Bell-inequality violations. Apart from entanglement and Bell-inequality violations, we consider also nonlocality as quantified by the nonlocal content of correlations, and provide several examples of anomalous behaviors, both in the bipartite and multipartite cases. In addition, we study the practical implications of these anomalies on the usefulness of noisy Greenberger-Horne-Zeilinger states as resources for nonlocality-based physical protocols given by communication complexity problems. There, we provide examples of quantum gains improving with the number of particles that coexist with exponentially-decaying entanglement and non-local contents.Comment: 6 pages, 4 figure