Quantum Entanglement

Entanglement in many-body systems

• Entanglement in fracton phases
• Entanglement in gapped boundaries of topological orders

Recent highlights:

• Detecting fractons by entanglement entropy (arXiv:1705.09300, w/ Bowen Shi)

We derive a lower bound for the non-local entanglement entropy, a generalization of the 2d topological entanglement entropy. We apply this lower bound to differentiate fracton phases from usual topological orders in 3d.

• Characterizing bulk and boundary excitations in 2+1-D topological orders using the "information convex" (arXiv:1801.01519, w/ Bowen Shi)

We show that "information convex", a convex set of reduced density matrices that minimizes energy in a subsystem, can be used to characterize topological excitations in a 2+1-D topological order, both in the bulk and on gapped boundaries. We demonstrate its power by applying it to both Abelian and non-Abelian topological orders.