1,235 research outputs found
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
Spin-Spin Interaction In Artificial Molecules With In-Plane Magnetic Field
We investigate theoretically the spin-spin interaction of two-electrons in
vertically coupled QDs as a function of the angle between magnetic field and
growth axis. Our numerical approach is based on a real-space description of
single-particle states in realistic samples and exact diagonalization of
carrier-carrier Coulomb interaction. In particular, the effect of the in-plane
field component on tunneling and, therefore, spin-spin interaction will be
discussed; the singlet-triplet phase diagram as a function of the field
strength and direction is drawn.Comment: Proc. of EP2DS-15, Nara, Japan - 6 pages, 4 figure
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
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