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Bosonic resonating valence bond wave function for doped Mott insulators
We propose a new class of ground states for doped Mott insulators in the
electron second-quantization representation. They are obtained from a bosonic
resonating valence bond (RVB) theory of the t-J model. At half filling, the
ground state describes spin correlations of the S=1/2 Heisenberg model very
accurately. Its spin degrees of freedom are characterized by RVB pairing of
spins, the size of which decreases continuously as holes are doped into the
system. Charge degrees of freedom emerge upon doping and are described by
twisted holes in the RVB background. We show that the twisted holes exhibit an
off diagonal long range order (ODLRO) in the pseudogap ground state, which has
a finite pairing amplitude, but is short of phase coherence. Unpaired spins in
such a pseudogap ground state behave as free vortices, preventing
superconducting phase coherence. The existence of nodal quasiparticles is also
ensured by such a hidden ODLRO in the ground state, which is
non-Fermi-liquid-like in the absence of superconducting phase coherence. Two
distinct types of spin excitations can also be constructed. The superconducting
instability of the pseudogap ground state is discussed and a d-wave
superconducting ground state is obtained. This class of pseudogap and
superconducting ground states unifies antiferromagnetism, pseudogap,
superconductivity, and Mott physics into a new state of matter.Comment: 28 pages, 5 figures, final version to appear in Phys. Rev.
Transmission eigenvalues and the bare conductance in the crossover to Anderson localization
We measure the field transmission matrix t for microwave radiation
propagating through random waveguides in the crossover to Anderson
localization. From these measurements, we determine the dimensionless
conductance, g, and the individual eigenvalues of the transmission
matrix whose sum equals g. In diffusive samples, the highest
eigenvalue, , is close to unity corresponding to a transmission of
nearly 100%, while for localized waves, the average of , is nearly
equal to g. We find that the spacing between average values of is
constant and demonstrate that when surface interactions are taken into account
it is equal to the inverse of the bare conductance.Comment: 5 pages, 5 figure
Extraction of the beam elastic shape from uncertain FBG strain measurement points
Aim of the present paper is the analysis of the strain along the beam that is equipped with Glass Fibers Reinforced Polymers (GFRP) with an embedded set of optical Fiber Bragg Grating sensors (FBG), in the context of a project to equip with these new structural elements an Italian train bridge. Different problems are attacked, and namely: (i)during the production process [1] it is difficult to locate precisely the FBG along the reinforcement bar, therefore the following question appears: How can we associate the strain measurements to the points along the bar? Is it possible to create a signal analysis procedure such that this correspondence is found?(ii)the beam can be inflected and besides the strain at some points, we would like to recover the elastic shape of the deformed beam that is equipped with the reinforcement bars. Which signal processing do we use to determine the shape of the deformed beam in its inflection plane?(iii)if the beam is spatially inflected, in two orthogonal planes, is it possible to recover the beam spatial elastic shape? Object of the paper is to answer to these questions
Exact solution of mean geodesic distance for Vicsek fractals
The Vicsek fractals are one of the most interesting classes of fractals and
the study of their structural properties is important. In this paper, the exact
formula for the mean geodesic distance of Vicsek fractals is found. The
quantity is computed precisely through the recurrence relations derived from
the self-similar structure of the fractals considered. The obtained exact
solution exhibits that the mean geodesic distance approximately increases as an
exponential function of the number of nodes, with the exponent equal to the
reciprocal of the fractal dimension. The closed-form solution is confirmed by
extensive numerical calculations.Comment: 4 pages, 3 figure
The genetic diversity and geographical separation study of Oncomelania hupensis populations in mainland China using microsatellite loci
© 2016 Guan et al. Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0
International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and
reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to
the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver
(http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. The attached file is the published version of the article.NHM Repositor
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