p x , y -orbital counterpart of graphene: Cold atoms in the honeycomb optical lattice
Congjun Wu,S. Das Sarma +1 more
TLDR
In this article, the ground-state properties of the interacting spinless fermions in the two-dimensional honeycomb optical lattice, which exhibit different features from those in the ${p}_{z}$-orbital system of graphene, were studied.Abstract:
We study the ground-state properties of the interacting spinless fermions in the ${p}_{x,y}$-orbital bands in the two-dimensional honeycomb optical lattice, which exhibit different features from those in the ${p}_{z}$-orbital system of graphene. In addition to two dispersive bands with Dirac cones, the tight-binding band structure exhibits another two completely flat bands over the entire Brillouin zone. With the realistic sinusoidal optical potential, the flat bands acquire a finite but much smaller bandwidth compared to the dispersive bands. The band flatness dramatically enhanced interaction effects giving rise to various charge and bond ordered states at commensurate fillings of $n=\frac{i}{6}(i=1--6)$. At $n=\frac{1}{6}$, the many-body ground states can be exactly solved as the close-packed hexagon states which can be stabilized even in the weakly interacting regime. The dimerization of bonding strength occurs at both $n=\frac{1}{2}$ and $\frac{5}{6}$, and the latter case is accompanied with the charge-density wave of holes. The trimerization of bonding strength and charge inhomogeneity appear at $n=\frac{1}{3},\frac{2}{3}$. These crystalline orders exhibit themselves in the noise correlations of the time-of-flight spectra.read more
Citations
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Nearly flatbands with nontrivial topology.
TL;DR: The theoretical discovery of a class of 2D tight-binding models containing nearly flatbands with nonzero Chern numbers, which may lead to the realization of fractional anomalous quantum Hall states and fractional topological insulators in real materials.
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Graphene-based materials for tissue engineering.
Su Ryon Shin,Su Ryon Shin,Yi-Chen Li,Hae Lin Jang,Parastoo Khoshakhlagh,Mohsen Akbari,Amir Nasajpour,Yu Shrike Zhang,Ali Tamayol,Ali Khademhosseini +9 more
TL;DR: Graphene and its chemical derivatives have been a pivotal new class of nanomaterials and a model system for quantum behavior and the opportunities in the usage of graphene-based materials for clinical applications are outlined.
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The rare two-dimensional materials with Dirac cones
TL;DR: In this article, the von Neumann-Wigner theorem is used to explain the scarcity of Dirac cones in 2D systems, which leads to rigorous requirements on the symmetry, parameters, Fermi level, and band overlap of materials to achieve Dirac cone.
Journal ArticleDOI
Multi-component quantum gases in spin-dependent hexagonal lattices
Parvis Soltan-Panahi,Julian Struck,Philipp Hauke,A. Bick,W. Plenkers,G. Meineke,Christoph Becker,Patrick Windpassinger,Maciej Lewenstein,Klaus Sengstock +9 more
TL;DR: In this paper, a honeycomb lattice structure has been realized for materials with hexagonal crystal symmetries, such as graphene or carbon nanotubes, which can be used to study a wide range of many-body effects.
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Chiral Spin Density Wave and d+id Superconductivity in the Magic-Angle-Twisted Bilayer Graphene.
TL;DR: In this article, a magic-angle-twisted bilayer graphene superconductor with two p_{x,y}-like Wannier orbitals on the superstructure honeycomb lattice was constructed via the Slater-Koster formulism by symmetry analysis.
References
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TL;DR: In this paper, the basic theoretical aspects of graphene, a one-atom-thick allotrope of carbon, with unusual two-dimensional Dirac-like electronic excitations, are discussed.
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TL;DR: In this paper, an experimental investigation of magneto-transport in a high-mobility single layer of Graphene is presented, where an unusual half-integer quantum Hall effect for both electron and hole carriers in graphene is observed.
Journal Article
Experimental Observation of Quantum Hall Effect and Berry's Phase in Graphene
TL;DR: An experimental investigation of magneto-transport in a high-mobility single layer of graphene observes an unusual half-integer quantum Hall effect for both electron and hole carriers in graphene.
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Observation of Bose-Einstein Condensation in a Dilute Atomic Vapor
TL;DR: A Bose-Einstein condensate was produced in a vapor of rubidium-87 atoms that was confined by magnetic fields and evaporatively cooled and exhibited a nonthermal, anisotropic velocity distribution expected of the minimum-energy quantum state of the magnetic trap in contrast to the isotropic, thermal velocity distribution observed in the broad uncondensed fraction.