2007/08/31 by Yue Yu, Ziqiang Wang · 1 citation
Physics and Astronomy · #Advanced Condensed Matter Physics #Physics of Superconductivity and Magnetism #Topological Materials and Phenomena #cond-mat.mes-hall #cond-mat.str-el
paper · pdf · doi:10.1209/0295-5075/84/57002
published as Europhys. Lett. 84, 57002 (2008) · 6 pages, 2 figures, published version
openalex publication_date 2008/11/25 · arxiv created 2009/01/16 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/30
Motivated by the work of Kitaev, we construct an exactly soluble spin-½ model on a honeycomb lattice whose ground states are identical to Δ 1 x p x +Δ 1 y p y + i (Δ 2 x p x +Δ 2 y p y )-wave paired fermions on a square lattice, with tunable paring order parameters. We derive a universal phase diagram for this general p -wave theory which contains a gapped A-phase and a topologically non-trivial B-phase. We show that the gapless condition in the B-phase is governed by a generalized inversion (G-inversion) symmetry under p x ↔ (Δ 1 y / Δ 1 x ) p y . The G-inversion symmetric gapless B-phase near the phase boundaries is described by (1+1)-dimensional gapless Majorana fermions in the asymptotic long-wavelength limit, i.e. the c =1/2 conformal field theory. The gapped B-phase has G-inversion symmetry breaking and is the weak pairing phase described by the Moore-Read Pfaffian. We show that in the gapped B-phase, vortex pair excitations are separated from the ground state by a finite energy gap.