Articles dans des revues à comité de lecture
|Entanglement Spectra of Complex Paired Superfluids|
|Dubail J., Read N.|
|PHYSICAL REVIEW LETTERS 107 (2011) 157001|
|DOI : 10.1103/PhysRevLett.107.157001|
We study the entanglement in various fully gapped complex paired states of fermions in two dimensions, focusing on the entanglement spectrum (ES), and using the Bardeen-Cooper-Schrieffer (BCS) form of the ground-state wave function on a cylinder. Certain forms of the pairing functions allow a simple and explicit exact solution for the ES. In the weak-pairing phase of l-wave paired spinless fermions (l odd), the universal low-lying part of the ES consists of vertical bar l vertical bar chiral Majorana fermion modes [or 2 vertical bar l vertical bar (l even) for spin-singlet states]. For vertical bar l vertical bar > 1, the pseudoenergies of the modes are split in general, but for all l there is a zero-pseudoenergy mode at a zero wave vector if the number of modes is odd. This ES agrees with the perturbed conformal field theory of the edge excitations. For more general BCS states, we show how the entanglement gap diverges as a model pairing function is approached.