Evolution of entanglement entropy in orbifold CFTs
Abstract
In this work we study the time evolution of the Rényi entanglement entropy for locally excited states created by twist operators in the cyclic orbifold (T^2){\hspace{0pt}}^n/{ {Z}_n} and the symmetric orbifold (T^2){\hspace{0pt}}^n/S_{n} . We find that when the square of its compactification radius is rational, the second Rényi entropy approaches a universal constant equal to the logarithm of the quantum dimension of the twist operator. On the other hand, in the nonrational case, we find a new scaling law for the Rényi entropies given by the double logarithm of time loglog t for the cyclic orbifold CFT.
Dedicated to John Cardy on his 70th birthday.
 Publication:

Journal of Physics A Mathematical General
 Pub Date:
 June 2017
 DOI:
 10.1088/17518121/aa6e08
 arXiv:
 arXiv:1701.03110
 Bibcode:
 2017JPhA...50x4001C
 Keywords:

 High Energy Physics  Theory;
 Condensed Matter  Statistical Mechanics
 EPrint:
 28 pages, 7 figures. Invited contribution to the special issue of J. Phys. A: "John Cardy's scaleinvariant journey in low dimensions: a special issue for his 70th birthday". v2: typos corrected, refs added, sec.5 improved. v3: affiliation, ref updated