Short-range correlations in a one-dimensional electron gas

We use the Singwi-Sjolander-Tosi-Land (SSTL) approximation to investigate the short-range correlations in a one-dimensional electron gas. We find out that the SSTL approximation satisfies the compressibility sum rule somewhat better than the more widely used Singwi-Tosi-Land-Sjolander approximation in the case of a one-dimensional electron gas

Spin-correlation effects in a one-dimensional electron gas

The Singwi-Sjolander-Tosi-Land (SSTL) approach is generalized to study the spin-correlation effects in a one-dimensional (1D) electron gas. It is shown that the SSTL approach yields different and interesting results compared with the more widely used Singwi-Tosi-Land-Sjolander (STLS) approach. We find out that the self-consistent field approaches, STLS and SSTL, predict a Bloch transition for 1D electron-gas systems at low electron densities

Interacting electrons in a 2D quantum dot

The exact numerical diagonalization of the Hamiltonian of a 2D circular quantum dot is performed for 2, 3, and 4 electrons.The results are compared with those of the perturbation theory.Our numerical results agree reasonably well for small values of the dimensionles coupling constant \lambda=a\over a_B where a is the dot radius and a_B is the effective Bohr radius.Exact diagonalization results are compared with the classical predictions, and they are found to be almost coincident for large \lambda values. PACS Numbers: 73.20.Dx, 73.61.-rComment: 12 pages, 5 postscript figure

Two-dimensional Yukawa Bose liquid: A Singwi-Tosi-Land-Sjölander study

We study the ground-state properties of a two-dimensional Yukawa boson liquid within the self-consistent scheme of Singwi et al. [Phys. Rev. 176, 589 (1968)]. The interaction potential being short ranged and having a soft core is the screened Coulomb interaction in two dimensions. We calculate the static structure factor and local-field corrections describing the short-range correlation effects, and compare our results with the Monte Carlo simulations

Vibrational modes in small Agn, Aun clusters: A first principle calculation

Although the stable structures and other physical properties of small Agn and Aun, were investigated in the literature, phonon calculations are not done yet. In this work, we present plane-wave pseudopotential calculations based on density-functional formalism. The effect of using the generalized gradient approximation (GGA) and local density approximation (LDA) to determine the geometric and electronic structure and normal mode calculations of Agn and Aun, is studied up to eight atoms. Pure Aun and Agn clusters favor planar configurations. We calculated binding energy per atom. We have also calculated the normal mode calculations and also scanning tunneling microscope (STM) images for small clusters for the first time. © 2009 World Scientific Publishing Company