From conformal to volume-law for the entanglement entropy in exponentially deformed critical spin 1/2 chains

An exponential deformation of 1D critical Hamiltonians gives rise to ground states whose entanglement entropy satisfies a volume-law. This effect is exemplified in the XX and Heisenberg models. In the XX case we characterize the crossover between the critical and the maximally entangled ground state in terms of the entanglement entropy and the entanglement spectrum.Comment: Accepted for the Special Issue: Quantum Entanglement in Condensed Matter Physics. 11 pages, 9 figures (with enhanced size to focus on the details) and new reference

Nuevo correo para alumnos: más capacidad, mejor acceso

El correo de los alumnos de la UC3M ha cambiado. Desde el 6 de mayo ha pasado al gestor de google, es decir, al sistema gmail. De esta forma, los correos tienen más capacidad y mejor acceso móvil

Entanglement in low-energy states of the random-hopping model

We study the low-energy states of the 1D random-hopping model in the strong disordered regime. The entanglement structure is shown to depend solely on the probability distribution for the length of the effective bonds $P(l_b)$, whose scaling and finite-size behavior are established using renormalization-group arguments and a simple model based on random permutations. Parity oscillations are absent in the von Neumann entropy with periodic boundary conditions, but appear in the higher moments of the distribution, such as the variance. The particle-hole excited states leave the bond-structure and the entanglement untouched. Nonetheless, particle addition or removal deletes bonds and leads to an effective saturation of entanglement at an effective block size given by the expected value for the longest bond

Resizing study of main and auxiliary engines of the container vessels and their contribution to the reduction of fuel consumption and GHG

ABSTRACT: The maritime industry has great potential for improving energy efficiency in both new builds and existing ships. It is, therefore, necessary to identify the areas where improvements can be made to reduce fuel consumption, and influence to the shipowners, shipyards and designers of ships on the need to implement these improvements in energetic efficiency and to achieve a reduction of between 25% and 75% of CO2 emissions as Third IMO GHG study 2014 provides, making ships even more environmentally friendly.Postprint (published version

Proyecto de Construcción: Variante oeste de Zafra. Tramo: EX 101 a N 432. Provincia de Badajoz

El presente proyecto tiene por objeto la definición y valoración de todas las obras necesarias para la realización del “Proyecto de Construcción. Variante oeste de Zafra. Tramo EX 101 a N 432.Provincia de Badajoz”.Universidad de Sevilla. Máster en Ingeniería de Caminos, Canales y Puerto

Indoor positioning for smartphones without infrastructure and user adaptable

Given that the classic solutions for positioning outdoors, such as GPS (Global Positioning System) or GNSS (Global Navigation Satellite System) do not work indoors, there have been emerging multiple alternatives for Indoor Location. Usually these solutions require extensive and complex installations, which involve high costs. In this thesis we present a robust indoor positioning solution for smartphones that maximizes location accuracy while minimizes the required infrastructure. We have considered two main modes of displacement: walking and in a vehicle. Our solution is robust to different users, allows them to carry the phone in different positions and allows to use the device freely while performing different daily activities, such as walking, driving , going up and down stairs, etc. We achieved that by developing a robust indoor positioning system that combines information from multiple sources such as radio frequency readings and inertial sensors