# Detecting topological orders in numerical simulations

Frank Pollmann, MPIPKS Dresden

12.12.2014 at 09:00

Matter occurs in various phases that are usually characterized in terms of symmetry breaking. A major discovery in the 1980s were the quantum Hall effects which exhibit a new kind of “topological” order. This order represents a class of exotic phases which cannot be described by spontaneous symmetry breaking. The lack of symmetry breaking order parameters makes it difficult to characterize these phases.

In this talk, I will show that numerical investigations of a many-body wavefunction can yield a remarkably complete characterization of different types of topological orders. A central tool is the ground state entanglement which encodes many of the essential features. I will show how characteristic properties of the topological excitations in spin liquids and fractional quantum Hall states can be extracted directly from the ground state wave functions.

A 450 - Theresienstr. 37