2021/11/18 by Luhang Yang, Phillip Weinberg, Yang, Luhang +3
Physics and Astronomy · #FOS: Physical sciences #Physics of Superconductivity and Magnetism #Quantum many-body systems #Strongly Correlated Electrons (cond-mat.str-el) #Theoretical and Computational Physics
paper · pdf · doi:10.48550/arxiv.2111.09798
openalex publication_date 2021/11/18 · openalex created_date 2021/11/22 · openalex updated_date 2026/07/28
We study a generalized quantum spin ladder with staggered long range interactions that decay as a power-law with exponent α. Using large scale quantum Monte Carlo (QMC) and the density matrix renormalization group (DMRG) simulations, we show that this model undergoes a transition from a rung-dimer phase characterized by a non-local string order parameter, to a symmetry broken Néel phase. We find evidence that the transition is second order.In the magnetically ordered phase, the spectrum exhibits gapless modes, while excitations in the gapped phase are well described in terms of triplons -- bound states of spinons across the legs. We obtain the momentum resolved spin dynamic structure factor numerically and find a well defined triplon band evolves into a gapless magnon dispersion through the transition. We further discuss the possibility of deconfined criticality in this model.