Schwinger boson mean field theory: numerics for the energy landscape and gauge excitations in two-dimensional antiferromagnets

Abstract

We perform some systematic numerical search for Schwinger boson mean field states on square and triangular lattice clusters. We look for possible inhomogeneous ground states as well as low-energy excited saddle points. The spectrum of the Hessian is also computed for each solution. On the square lattice we find gapless U(1) gauge modes in the non-magnetic phase. In the Z_2 liquid phase of the triangular lattice we identify the topological degeneracy as well as vison states.

14 pages, 24 color figures. To appear in Phys. Rev. B. Changes: Section on kagome was removed (judged too incomplete by the one referee). Expanded conclusion. Various minor changes

References in corpus (7)

• Spin Liquid States on the Triangular and Kagome Lattices: A Projective Symmetry Group Analysis of Schwinger Boson States
• Mott Insulators of Ultracold Fermionic Alkaline Earth Atoms: Underconstrained Magnetism and Chiral Spin Liquid
• The kagome antiferromagnet: a chiral topological spin liquid ?
• Topological liquids and valence cluster states in two-dimensional SU(N) magnets
• Symplectic N and time reversal in frustrated magnetism
• Flux expulsion and greedy bosons: frustrated magnets at large N
• Sign structures for short-range RVB states on small kagome clusters

Cited by in corpus (8)

• Spin liquid nature in the Heisenberg $J_1$-$J_2$ triangular antiferromagnet
• Time-reversal-symmetry-breaking chiral spin liquids: a projective symmetry group approach of bosonic mean-field theories
• Topological Nematic Spin Liquid on the Square-Kagome Lattice
• Heisenberg antiferromagnet on Cayley trees: low-energy spectrum and even/odd site imbalance
• Quantum spin liquid ground states of the Heisenberg-Kitaev model on the triangular lattice
• Thermal Hall effect from two-dimensional Schwinger-boson gas with Rashba spin-orbit interaction: application to ferromagnets with in-plane Dzyaloshinskii-Moriya interaction
• Schwinger boson mean field perspective on emergent spins in diluted Heisenberg antiferromagnets
• Schwinger boson study of the $J_1$-$J_2$-$J_3$ kagome Heisenberg antiferromagnet with Dzyaloshinskii-Moriya interactions