Strong correlation effects and optical conductivity in electron doped cuprates

We demonstrate that most features ascribed to strong correlation effects in various spectroscopies of the cuprates are captured by a calculation of the self-energy incorporating effects of spin and charge fluctuations. The self energy is calculated over the full doping range of electron-doped cuprates from half filling to the overdoped system. The spectral function reveals four subbands, two widely split incoherent bands representing the remnant of the split Hubbard bands, and two additional coherent, spin- and charge-dressed in-gap bands split by a spin-density wave, which collapses in the overdoped regime. The incoherent features persist to high doping, producing a remnant Mott gap in the optical spectra, while transitions between the in-gap states lead to pseudogap features in the mid-infrared.Comment: 5 pages, 4 figure

Lattice calculations on the spectrum of Dirac and Dirac-K\"ahler operators

We present a matrix technique to obtain the spectrum and the analytical index of some elliptic operators defined on compact Riemannian manifolds. The method uses matrix representations of the derivative which yield exact values for the derivative of a trigonometric polynomial. These matrices can be used to find the exact spectrum of an elliptic operator in particular cases and in general, to give insight into the properties of the solution of the spectral problem. As examples, the analytical index and the eigenvalues of the Dirac operator on the torus and on the sphere are obtained and as an application of this technique, the spectrum of the Dirac-Kahler operator on the sphere is explored.Comment: 11 page

Effect of different derivatives of paraffin waxes on crystallization of eutectic mixture of cocoa butter-coconut oil

Paraffin wax is a mixture of numerous unbranched hydrocarbons used frequently for various purposes: to improve the shelf life of products containing lipid system and develop more shiny products. However, because of its complex nature, the effect of such molecular structure on the solid phase behavior of lipids is hardly unstated. Hence in our study, we focus on understanding the impact of derivatives of paraffin wax on the lipid system. In the current work, three unbranched derivatives of paraffin wax: Eicosane C (20), Pentacosane C (25) and Triacontane C (30) were selected as additives. These n-alkanes are specifically added to the eutectic mixture of cocoa butter (CB) and coconut oil (CO) (E(CB-CO)) to observe the effect on thermal, morphological, rheological properties and crystallization kinetics with respect to the carbon chain length. Results from our study illustrate that melting and crystallization temperature, storage modulus and solid fat content (SFC) increases after the addition of 1 wt% of C (20), C (25). In contrast, there is a phase separation for 1 wt% C (30). Further similar study with addition of n-alkanes to pure CB and CO reveals that the interaction of n-alkanes with E(CB-CO) is dominated by the interaction of n-alkanes with CO instead of CB. Therefore, our findings provide insight into the effect of addition of n-alkanes having different carbon chain length and their respective concentration on crystallization process of CB and CO. This will definitely help to design the processes for products containing such model systems

High-Velocity Estimates and Inverse Scattering for Quantum N-Body Systems with Stark Effect

In an N-body quantum system with a constant electric field, by inverse scattering, we uniquely reconstruct pair potentials, belonging to the optimal class of short-range potentials and long-range potentials, from the high-velocity limit of the Dollard scattering operator. We give a reconstruction formula with an error term.Comment: In this published version we have added remarks and we have edited the pape