Fractional Chern Insulators
Emil Bergholtz
 Freie Universitat Berlin
Abstract
A large number of recent work points to the emergence of intriguing analogues of fractional quantum Hall states in two-dimensional lattice models due to effective interactions in nearly flat bands with Chern number C=1. In principle, this opens up a number of intriguing possibilities including lattice realizations of quantum Hall phenomena and anyons at room temperature. Here, I will discuss three related topics. First, I will discuss for which filling fractions there is numerical evidence for fractional Chern insulators (incompressible states), including new evidence for several abelian hierarchy of states, and also point out some important differences compared to conventional Landau level physics and the emergence of competing compressible phases. Second, I will introduce a minimal solvable model describing a “thin-torus” version of a fractional Chern insulator. Third, I will discuss the physics in flat bands with higher Chern number and possible realizations thereof in quasi-two-dimensional slabs of pyrochlore based transition metal oxides. 
　 
 
 
Time: Jun. 5th, 2012 (Tuesday) 14:30
Place: IOP D-210 Conference Room
Contact: Ying Deng 82649414