Wydarzenia

Seminarium "Coherence-Correlations-Complexity" (KFT, PWr)

Fractional Chern Insulator on Lieb Lattice

Błażej Jaworowski

Katedra Fizyki Teoretycznej WPPT PWr

Fractional Chern Insulator (FCI) is a phase of correlated electrons on a lattice similar to fractional quantum Hall effect. In FCI, the role of a Landau level is played by topologically nontrivial nearly-flat energy band. It has been numerically proven that FCI exists on a number of abstract model lattices, such as kagome, honeycomb, and checkerboard. Here, we propose realization of FCI on a new lattice: the Lieb lattice. By numerical investigation using configuration interaction method involving calculation of energy spectra, spectral flow and quasihole excitation spectrum, we prove that for filling factor 1/3, FCI is the ground state of the system for a wide range of model parameters.