Dr. Tarun Grover

UC Berkeley

Quantum Entanglement and Strongly Correlated Topological Phases of Matter

Strong interactions can give rise to new phases of quantum matter that do not order even at absolute zero temperature and are therefore difficult to characterize, both theoretically and experimentally. In this talk, I will illustrate the unique view provided by many-body quantum entanglement on a large class of such interacting phases. In particular, I will explain that for "topologically ordered" phases, entanglement entropy can never be expressed as a sum of local terms. Such non-locality in entanglement can be used to detect as well as construct new topologically ordered systems.

Further, I will demonstrate that the entanglement can be used to extract robust properties of fractionalized excitations ("anyons") in an arbitrary topologically ordered phase, a task that is practically impossible to achieve by other means. I will also discuss an example where the entanglement can be used to detect emergent gapless fermions in a system composed only of bosons.