We consider the spin ?/2 analogue of the XXZ quantum spin chain. We compute the entanglement entropy S associated with splitting the infinite chain into two semi-infinite pieces. In the scaling limit, we find . Here ? is the correlation length and c? = 3?/(?+2) is the central charge associated with the Wess-Zumino-Witten (WZW) model at level ?. ln(g) is the boundary entropy of the WZW model. Our result extends previous observations and suggests that this is a simple and perhaps rather general way both of extracting the central charge of the ultraviolet conformal field theory (CFT) associated with the scaling limit of a solvable lattice model, and of matching lattice and CFT boundary conditions. © IOP Publishing Ltd and SISSA.
|Number of pages||7|
|Journal||Journal of Statistical Mechanics: Theory and Experiment|
|Publication status||Published - 1 Mar 2006|
- Algebraic structures of integrable models
- Entanglement in extended quantum systems (theory)
- Integrable spin chains (vertex models)
- Solvable lattice models