Many Body Quantum Entanglement and Topological Phases of Matter

 

Ashwin Vishwanath (Berkeley)

10AM   CP179

Abstract:  In contrast to symmetry broken states that are described by a local order parameter, the ground states of topological quantum phases are notoriously hard to characterize. We discuss many-body quantum entanglement as a tool to study topological states - both of the `integer' variety that are connected to free fermions (such as integer quantum hall states and topological insulators) as well as the strongly interacting `fractional' states (such as fractional quantum hall states). Time permitting I will discuss a scheme that allows for a determination of the braiding properties of excitations in a fractional topological phase (modular S-matrix), and numerically demonstrate its applicability for model wavefunctions.