Three interacting atoms in a one-dimensional trap: A benchmark system for computational approaches

We provide an accurate calculation of the energy spectrum of three atoms interacting through a contact force in a one-dimensional harmonic trap, considering both spinful fermions and spinless bosons. We use fermionic energies as a benchmark for exact-diagonalization technique (also known as full configuration interaction), which is found to slowly converge in the case of strong interatomic attraction.Comment: To appear in Journal of Physics B: Atomic, Molecular and Optical Physic

Pairing of few Fermi atoms in one dimension

We study a few Fermi atoms interacting through attractive contact forces in a one-dimensional trap by means of numerical exact diagonalization. From the combined analysis of energies and wave functions of correlated ground and excited states we find evidence of BCS-like pairing even for very few atoms. For moderate interaction strength, we reproduce the even-odd oscillation of the separation energy observed in [G. Zuern, A. N. Wenz, S. Murmann, A. Bergschneider, T. Lompe, and S. Jochim, Phys. Rev. Lett. 111, 175302 (2013)]. For strong interatomic attraction the arrangement of dimers in the trap differs from the homogeneous case as a consequence of Pauli blockade in real space.Comment: Major revision to appear in Physical Review

Correlation Effects in Quantum Dot Wave Function Imaging

We demonstrate that in semiconductor quantum dots wave functions probed by imaging techniques based on local tunneling spectroscopies like STM show characteristic signatures of electron-electron Coulomb correlation. We predict that such images correspond to ``quasi-particle'' wave functions which cannot be computed by standard mean-field techniques (density functional theory, Hartree-Fock) in the strongly correlated regime corresponding to low electron density. From the configuration-interaction solution of the few-particle problem for prototype dots, we find that quasi-particle wave function images may display signatures of Wigner crystallization.Comment: Latex 2e + jjap2 style version 1.0. 4 pages, 3 postscript figures. Submitted to the Japanese Journal of Applied Physics as Proceeding of STM05 Conference, Sapporo, Japan, July 3-8, 200

Coherent exciton transport in semiconductors

We review the topic of Bose-Einstein condensation of excitons in semiconductors, focusing on the signatures of the macroscopic order of the exciton condensate.Comment: Some references were updated with respect to the published version. appears as Chapter 19 in Novel Superfluids Volume 2, edited by K. H. Bennemann and J. B. Ketterson, International Series of Monographs on Physics no. 157, pages 423-474 (Oxford University Press, Oxford, 2014

The Crossover between Liquid and Solid Electron Phases in Quantum Dots: A Large-Scale Configuration-Interaction Study

We study the crossover between liquid and solid electron phases in a two-dimensional harmonic trap as the density is progressively diluted. We infer the formation of geometrically ordered phases from charge distributions and pair correlation functions obtained via a large scale configuration interaction calculation.Comment: LaTeX 2e, Elsevier style. Four pages, two b/w postscript figures. Submitted to Computer Physics Communications as a proceeding of Conference on Computational Physics, Genova 200