—Staggering computational and algorithmic advances in recent years now make possible systematic Quantum Monte Carlo (QMC) simulations of high temperature (high-Tc) su-perconductivity in a microscopic model, the two dimensional (2D) Hubbard model, with parameters relevant to the cuprate materials. Here we report the algorithmic and computational advances… (More)
How do we estimate the number of objects in a set? Two types of visual representations might underlie this ability - an unsegmented visual image or a segmented collection of discrete objects. We manipulated whether individual objects were isolated from each other or grouped into pairs by irrelevant lines. If number estimation operates over an unsegmented… (More)
The purpose of this paper is (i) to present a generic and fully functional implementation of the density-matrix renormalization group (DMRG) algorithm, and (ii) to describe how to write additional strongly-correlated electron models and geometries by using templated classes. Besides considering general models and geometries, the code implements Hamiltonian… (More)
The Schwinger model is studied in a finite lattice by means of the P-representation. The vacuum energy, mass gap and chiral condensate are evaluated showing good agreement with the expected values in the continuum limit.
We investigate mechanisms of balancing selection by extending two deterministic models of selection in a one-locus two-allele genetic system to allow for frequency-dependent fitnesses. Specifically we extend models of constant selection to allow for general frequency-dependent fitness functions for sex-dependent viabilities and multiplicative fertilities,… (More)
ii Contents Abstract i Resumen iii Acknowledgments v Agradecimientos vii 1 Introduction 1 1.
Mn-doped GaAs is studied with a real-space Hamiltonian on an fcc lattice that reproduces the valence bands of undoped GaAs. Large-scale Monte Carlo (MC) simulations on a Cray XT3, using up to a thousand nodes, were needed. Spin-orbit interaction and the random distribution of the Mn ions are considered. The hopping amplitudes are functions of the GaAs… (More)
GOAL This paper describes the development and testing of various position sensing systems (PSSs) for miniaturized long-term applications with a focus on their validation in a total artificial heart (TAH). After a short description of the TAH's functioning principle, the special requirements for the PSS resulting from the application in a TAH are… (More)