183 research outputs found
Metamagnetism in the 2D Hubbard Model with easy axis
Although the Hubbard model is widely investigated, there are surprisingly few
attempts to study the behavior of such a model in an external magnetic field.
Using the Projector Quantum Monte Carlo technique, we show that the Hubbard
model with an easy axis exhibits metamagnetic behavior if an external field is
turned on. For the case of intermediate correlations strength , we observe a
smooth transition from an antiferromagnetic regime to a paramagnetic phase.
While the staggered magnetization will decrease linearly up to a critical field
, uniform magnetization develops only for fields higher than .Comment: RevTeX 5 pages + 2 postscript figures (included), accepted for PRB
Rapid Communication
Radioactive decays at limits of nuclear stability
The last decades brought an impressive progress in synthesizing and studying
properties of nuclides located very far from the beta stability line. Among the
most fundamental properties of such exotic nuclides, usually established first,
is the half-life, possible radioactive decay modes, and their relative
probabilities. When approaching limits of nuclear stability, new decay modes
set in. First, beta decays become accompanied by emission of nucleons from
highly excited states of daughter nuclei. Second, when the nucleon separation
energy becomes negative, nucleons start to be emitted from the ground state.
Here, we present a review of the decay modes occurring close to the limits of
stability. The experimental methods used to produce, identify and detect new
species and their radiation are discussed. The current theoretical
understanding of these decay processes is overviewed. The theoretical
description of the most recently discovered and most complex radioactive
process - the two-proton radioactivity - is discussed in more detail.Comment: Review, 68 pages, 39 figure
Sur une interprétation appligarle au phénomène de Faraday et au phénomène de Zeeman
Pas de Résumé disponibl
Absorption de la lumière et phénomènes magnéto-optiques dans les sels de terres rares aux températures de liquéfaction et de solidification de l'hydrogène
Pas de Résumé disponibl
Flexible Wire‐Shaped Perovskite Photodetector via Joule Heating for Improved Crystallization and Performance
Organolead triiodide perovskite (CH3NH3PbI3) is used extensively as the absorber material for both solar cells and photodetectors; however, the reported photodetectors are all planar and flexible planar devices. To the best of knowledge the first flexible wire-shaped perovskite photodetector is reported. The performance of the wire-shaped perovskite photodetector on carbon nanotube yarn (CNY) critically depends on the surface geometry and annealing conditions. The use of joule heating method for uniform control of temperature on CNY surface results in smooth perovskite crystalline films, which are used to produce self-powering photodetectors with strong responsivity (10.2 A W−1), detectivity (1.76 × 1011 J), and Ilight/Idark (45). This development displays the role of joule heating in the annealing process and demonstrates a cheap, repeatable method for the fabrication of self-powered perovskite photodetectors
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