2008/10/31 by Miguel Ibáñez-Berganza, Miguel Ibanez, Jon Links +3 · 2 citations
Physics and Astronomy · #Exact solutions in general relativity #Ground state #Mathematical physics #Pairing #Phase (matter) #Phase diagram #Physics #Physics of Superconductivity and Magnetism #Quantum many-body systems #Quantum mechanics #Superconductivity #Topological Materials and Phenomena #cond-mat.supr-con #hep-th #nucl-th #quant-ph
paper · pdf · doi:10.1103/physrevb.79.180501
published as Phys. Rev. B79:180501,2009 · 4 pages, 2 figures. Discussion on winding numbers added. Accepted in Phys Rev B
arxiv created 2009/04/21 · openalex publication_date 2009/05/01 · arxiv updated 2011/04/28 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We present the exact Bethe ansatz solution for the two-dimensional BCS pairing Hamiltonian with px+ipy symmetry. Using both mean-field theory and the exact solution we obtain the ground-state phase diagram parametrized by the filling fraction and the coupling constant. It consists of three phases that are denoted weak-coupling BCS, weak pairing, and strong pairing. The first two phases are separated by a topologically protected line where the exact ground state is given by the Moore-Read pfaffian state. In the thermodynamic limit the ground-state energy is discontinuous on this line. The other two phases are separated by the critical line, also topologically protected, previously found by Read and Green. We establish a duality relation between the weak and strong pairing phases, whereby ground states of the weak phase are ``dressed'' versions of the ground states of the strong phase by zero energy (Moore-Read) pairs and characterized by a topological order parameter.