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The unusual quantum Hall effect (QHE) in graphene is often discussed in terms of Dirac fermions moving with a linear dispersion relation. The same phenomenon will be explained in terms of the more traditional composite bosons, which move with a linea r dispersion relation. The electron (wave packet) moves easier in the direction [1,1,0,c-axis] = [1,1,0] of the honeycomb lattice than perpendicular to it, while the hole moves easier in [0,0,1]. Since electrons and holes move in different channels, the number densities can be high especially when the Fermi surface has necks. The strong QHE arises from the phonon exchange attraction in the neighborhood of the neck Fermi surfaces. The plateau observed for the Hall conductivity and the accompanied resistivity drop is due to the Bose-Einstein condensation of the c-bosons, each forming from a pair of one-electron--two-fluxons c-fermions by phonon-exchange attraction.
A quantum statistical theory is developed for a fractional quantum Hall effects in terms of composite bosons (fermions) each of which contains a conduction electron and an odd (even) number of fluxons. The cause of the QHE is by assumption the phonon exchange attraction between the conduction electron (electron, hole) and fluxons (quanta of magnetic fluxes). We postulate that c-fermions with emph{any} even number of fluxons have an effective charge (magnitude) equal to the electron charge $e$. The density of c-fermions with $m$ fluxons, $n_phi^{(m)}$, is connected with the electron density $n_{mathrm e}$ by $n_phi^{(m)}=n_{mathrm e}/m$, which implies a more difficult formation for higher $m$, generating correct values $me^2/h$ for the Hall conductivity $sigma_{mathrm H}equiv j/E_{mathrm H}$. For condensed c-bosons the density of c-bosons-with-$m$ fluxons, $n_phi^{(m)}$, is connected with the boson density $n_0$ by $n_phi^{(m)}=n_0/m$. This yields $sigma_{mathrm H}=m,e^2/h$ for the magnetoconductivity, the value observed of the QHE at filling factor $ u=1/m$ ($m=$odd numbers). Laughlins theory and results about the fractional charge are not borrowed in the present work.
Two atoms in an optical lattice may be made to interact strongly at higher partial waves near a Feshbach resonance. These atoms, under appropriate constraints, could be bosonic or fermionic. The universal $l=2$ energy spectrum for such a system, with a caveat, is presented in this paper, and checked with the spectrum obtained by direct numerical integration of the Schrodinger equation. The results reported here extend those of Yip for p-wave resonance (Phys. Rev. A {bf 78}, 013612 (2008)), while exploring the limitations of a universal expression for the spectrum for the higher partial waves.
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