Mirages and enhanced magnetic interactions in quantum corrals

We develop a theory for the interactions between magnetic impurities in nanoscopic systems. The case of impurities in quantum corrals built on the (111) Cu surface is analyzed in detail. For elliptical corrals with one impurity, clear magnetic mirages are obtained. This leads to an enhancement of the inter-impurity interactions when two impurities are placed at special points in the corral. We discuss the enhancement of the conduction electron response to the local perturbation in other nanoscopic systems.Comment: 7 pages, 5 figure

U.S. Federal Reserve Monetary Policy and the Fisrt Crisis of Securitization: Mexico and Latin America, 1994-1995

The decisions of the Federal Reserve of United States (Fed)determinig interest rates have played a critical role in capital inflows/outflows toward Mexico and Latin America. The causal relationship that exists between the Fed and emergin markets is quite close; a clear example of this is the first crisis of securitization on the global level, which originated in Mexico in 1994. The monetary policy of the Fed supported the expansion of U.S. investment banks and some institutional investors, thus creating not only an enormous bubble in Mexico and other local financial markets in Latin America through the expansion of portfolio investment, but also succesive financial crises during the 1990s when those financial capital flows reversed themseleves

Magnetic field induced lattice anomaly inside the superconducting state of CeCoIn5_5: evidence of the proposed Fulde-Ferrell-Larkin-Ovchinnikov state

We report high magnetic field linear magnetostriction experiments on CeCoIn$_5$ single crystals. Two features are remarkable: (i) a sharp discontinuity in all the crystallographic axes associated with the upper superconducting critical field $B_{c2}$ that becomes less pronounced as the temperature increases; (ii) a distinctive second order-like feature observed only along the c-axis in the high field (10 T $\lesssim B \leq B_{c2}$) low temperature ($T \lesssim$ 0.35 K) region. This second order transition is observed only when the magnetic field lies within 20$^o$ of the ab-planes and there is no signature of it above $B_{c2}$, which raises questions regarding its interpretation as a field induced magnetically ordered phase. Good agreement with previous results suggests that this anomaly is related to the transition to the Fulde-Ferrel-Larkin-Ovchinnikov superconducting state.Comment: 3 figures, 5 page

Teor de metais pesados na cultura da aveia preta em função da aplicação superficial de resíduos urbanos e industriais, no sistema plantio direto.

Projeto/Plano de Ação: 01.09.10103-04