arXiv:cond-mat/9407014 · Physical review. B, Condensed matter
Fractional quantum Hall effect on a lattice
Fakher F. Assaad, S. Biskamp
Abstract
Starting from the Hofstadter butterfly, we define lattice versions of Landau levels as well as a continuum limit that ensures they scale to continuum Landau levels. By including a next-neighbor repulsive interaction and projecting onto the lowest-lattice Landau level, we show that incompressible ground states exist on the lattice at odd-filling fractions. Already for values of ${\mathit{l}}_{0}$/a\ensuremath{\sim}2 where ${\mathit{l}}_{0}$ (a) is the magnetic length (lattice constant), the continuum \ensuremath{\nu}=1/3 Laughlin state is reproduced with perfect accuracy. Hence, a is argued to be an irrelevant length scale.