2017/09/20 by Xi Luo, Feng Tang, Luo, Xi +5
Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #FOS: Physical sciences #High Energy Physics - Theory (hep-th) #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Quantum Mechanics and Non-Hermitian Physics #Topological Materials and Phenomena
paper · pdf · doi:10.48550/arxiv.1709.06947
openalex publication_date 2017/09/20 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We present two band models for free fermion with charge conjugation symmetry in three dimensions. Without time reversal symmetry (TRS), the weak pairing gapless A-phase is a Majorana fermion px+ipy wave FFLO state while the strong pairing gapped B-phase belongs to topologically trivial Class D. With TRS, there is a Majorana fermion B-phase belonging to Class DIII with a non-zero Hopf invariant. The TRS A-phase is also a Majorana fermion FFLO state with TRS. The surface states of the TRS B-phase are either a valley-momentum locked Majorana-Dirac cone or a linear-quadratic mixed cone for a specific surface. The surface states of the A-phase on one surface are topologically nontrivial, either having ℤ or ℤ2 invariant depending on whether the system is TRS or not. The edge states of that surface are gapless Majorana modes. The Majorana fermion gapless FFLO states can be realized in critical Weyl semimetals (WSM) in which dual single Weyl nodes form dipoles and are nearly annihilated. The gapped B-phase emerges when Weyl node dipoles are about to be created. The WSM TaAs-family, a type-II WSM series MoxW1-xTe2-family, possible WSM La/LuBi1-x SbxTe3 and topological crystalline insulators Sn1-xPbx(Te,Se) are candidates to be manipulated into these critical states based on Majorana fermion models.