2017/12/18 by Edward O'Brien, Edward E. O’Brien, Paul Fendley · 1 voice · 2 citations
Physics and Astronomy · #Complex Network Analysis Techniques #Condensed matter physics #Ising model #Lattice (music) #Mathematical physics #Opinion Dynamics and Social Influence #Phase diagram #Physics #Quantum many-body systems #Quantum mechanics #Square-lattice Ising model #Supersymmetry #Theoretical physics #Tricritical point #cond-mat.stat-mech #cond-mat.str-el #hep-th
paper · pdf · doi:10.1103/physrevlett.120.206403
published as Phys. Rev. Lett. 120, 206403 (2018) · 5+3 pages. v2: added three short appendices, including numerics comparing various four-fermi perturbations
arxiv published 2017/12/18 · openalex created_date 2018/01/05 · openalex publication_date 2018/05/17 · arxiv created 2018/10/03 · arxiv updated 2018/10/04 · openalex updated_date 2026/08/05
We introduce and analyze a quantum spin or Majorana chain with a tricritical Ising point separating a critical phase from a gapped phase with order-disorder coexistence. We show that supersymmetry is not only an emergent property of the scaling limit but also manifests itself on the lattice. Namely, we find explicit lattice expressions for the supersymmetry generators and currents. Writing the Hamiltonian in terms of these generators allows us to find the ground states exactly at a frustration-free coupling. These confirm the coexistence between two (topologically) ordered ground states and a disordered one in the gapped phase. Deforming the model by including explicit chiral symmetry breaking, we find the phases persist up to an unusual chiral phase transition where the supersymmetry becomes exact even on the lattice.