Berry phase investigation of spin-S ladders

Abstract

We investigate the properties of antiferromagnetic spin-S ladders with the help of local Berry phases defined by imposing a twist on one or a few local bonds. In gapped systems with time reversal symmetry, these Berry phases are quantized, hence able in principle to characterize different phases. In the case of a fully frustrated ladder where the total spin on a rung is a conserved quantity that changes abruptly upon increasing the rung coupling, we show that two Berry phases are relevant to detect such phase transitions: the rung Berry phase defined by imposing a twist on one rung coupling, and the twist Berry phase defined by twisting the boundary conditions along the legs. In the case of non-frustrated ladders, we have followed the fate of both Berry phases when interpolating between standard ladders and dimerized spin chains. A careful investigation of the spin gap and of edge states shows that a change of twist Berry phase is associated to a quantum phase transition at which the bulk gap closes, and at which, with appropriate boundary conditions, edge states appear or disappear, while a change of rung Berry phase is not necessarily associated to a quantum phase transition. The difference is particularly acute for regular ladders, in which the twist Berry phase does not change at all upon increasing the rung coupling from zero to infinity while the rung Berry phase changes 2S times. By analogy with the fully frustrated ladder, these changes are interpreted as cross-overs between domains in which the rungs are in different states of total spin from 0 in the strong rung limit to 2S in the weak rung limit. This interpretation is further supported by the observation that these cross-overs turn into real phase transitions as a function of rung coupling if one rung is strongly ferromagnetic, or equivalently if one rung is replaced by a spin 2S impurity.

9 pages, 10 figures The second version has been entirely rewritten

References in corpus (11)

• The ALPS project release 1.3: open source software for strongly correlated systems
• Topological Classification of Gapped Spin Chains :Quantized Berry Phase as a Local Order Parameter
• Topological Order, Dimerization, and Spinon Deconfinement in Frustrated Spin Ladders
• Degeneracy and Consistency Condition of Berry phases: Gap Closing under the Twist
• Quantum Criticality in Dimerized Spin Ladders
• Topological Identification of Spin-1/2 Two-Leg Ladder with Four-Spin Ring Exchange
• DMRG study of the Bond Alternating \textbf{S}=1/2 Heisenberg ladder with Ferro-Antiferromagnetic couplings
• Edge states of Spin-1/2 Two-Leg Ladder with Four-Spin Ring Exchange
• Critical Lines and Massive Phases in Quantum Spin Ladders with Dimerization
• Twisted Order Parameter applied to Dimerized Ladders
• Topological quantum phase transition in the BEC-BCS crossover phenomena

Cited by in corpus (15)

• $Z_N$ Berry Phases in Symmetry Protected Topological Phases
• Topological Order Parameters of the Spin-1/2 Dimerized Heisenberg Ladder in Magnetic Field
• Constructing Landau framework for topological order: Quantum chains and ladders
• Phase diagram of the alternating-spin Heisenberg chain with extra isotropic three-body exchange interactions
• Polarization amplitude near quantum critical points
• Sequential quantum phase transitions in $J_1$-$J_2$ Heisenberg chains with integer spins ($S>1$): Quantized Berry phase and valence-bond solids
• Topological pump and bulk-edge-correspondence in an extended Bose-Hubbard model
• Plateau transitions of spin pump and bulk-edge correspondence
• Rigorous decoupling between edge states in frustrated spin chains and ladders
• Topological phases in two-legged Heisenberg ladders with alternating interactions
• Magnetization process in a frustrated plaquette dimerized ladder
• Critical properties of a comb lattice
• Exploring Percolative Landscapes: Infinite Cascades of Geometric Phase Transitions
• $Z_2\times Z_2$ symmetry and $Z_4$ Berry phase of bosonic ladder
• Deconfined criticality for the two-dimensional quantum S=1-spin model with the three-spin and biquadratic interactions