Inducing and controlling magnetism in the honeycomb lattice through a harmonic trapping potential

Abstract

We study strongly interacting ultracold spin-1/2 fermions in a honeycomb lattice in the presence of a harmonic trap. Tuning the strength of the harmonic trap we show that it is possible to confine the fermions in artificial structures reminiscent of graphene nanoflakes in solid state. The confinement on small structures induces magnetic effects which are absent in a large graphene sheet. Increasing the strength of the harmonic potential we are able to induce different magnetic states, such as a Néel-like antiferromagnetic or ferromagnetic states, as well as mixtures of these basic states. The realization of different magnetic patterns is associated with the terminations of the artificial structures, in turn controlled by the confining potential.

Smart local orbitals for efficient calculations within density functional theory and beyond

“…Moreover, the combination of the subdiagonalization and embedding procedures could be employed to define effective tight-binding models on a reduced basis set. The latter is appealing, e.g., for tight-binding parametrizations of real materials 58,59 and for methods suitable to address strong electronic correlations, such as GW and the dynamical meanfield theory 5 (DMFT) and its real-space extension 60 aiming at the description of inhomogeneous [61][62][63] and nanoscopic systems. 8,25,26,56,[64][65][66][67][68][69][70][71][72] In particular, due to their spatial localization, the LOs represent a possible alternative to Wannier orbitals 15 or natural orbitals 73 to define local Coulomb interaction parameters in the framework of a DFT+DMFT and GW+DMFT approaches (for recent reviews of these topics see, e.g., Refs.…”

Resistivity saturation in semi-conducting polyacetylene molecular wires

“…Such approaches can describe correlation phenomena at all energy scales, including site-selective Mott physics [52][53][54][55] and temperature-dependent phenomena [23,24,[56][57][58][59][60], and have been successfully applied to describe the electronic [48,54,58,[61][62][63][64][65] and transport [21, 22, 40-42, 52, 53, 55-57, 59, 66-70] properties of molecular and nanoscopic systems.…”

Electrode effects on the observability of destructive quantum interference in single-molecule junctions

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