Topological quantum paramagnet in a quantum spin ladder

Abstract

It has recently been found that bosonic excitations of ordered media, such as phonons or spinons, can exhibit topologically nontrivial band structures. Of particular interest are magnon and triplon excitations in quantum magnets, as they can easily be manipulated by an applied field. Here we study triplon excitations in an S=1/2 quantum spin ladder and show that they exhibit nontrivial topology, even in the quantum-disordered paramagnetic phase. Our analysis reveals that the paramagnetic phase actually consists of two separate regions with topologically distinct triplon excitations. We demonstrate that the topological transition between these two regions can be tuned by an external magnetic field. The winding number that characterizes the topology of the triplons is derived and evaluated. By the bulk-boundary correspondence, we find that the non-zero winding number implies the presence of localized triplon end states. Experimental signatures and possible physical realizations of the topological paramagnetic phase are discussed.

arXiv comment6+4 pages; References, footnotes, small clarification added in conclusions and suppl. mat (v2); Minor modifications, close to published version (v3)

References in corpus (34)

• Topological Insulators
• Topological insulators and superconductors
• Quantum Spin Hall Insulator State in HgTe Quantum Wells
• Topological Photonics
• Classification of topological insulators and superconductors in three spatial dimensions
• Classification of topological quantum matter with symmetries
• First observation of Spin-Momentum Helical Locking in Bi2Se3 and Bi2Te3, demonstration of Topological-Order at 300K and a realization of topological-transport-regime
• Surprises on the Way from 1D to 2D Quantum Magnets: the Novel Ladder Materials
• Lasing in topological edge states of a 1D lattice
• The building blocks of magnonics
• Direct observation of Dirac cones and a flatband in a honeycomb lattice for polaritons
• Physics of three dimensional bosonic topological insulators: Surface Deconfined Criticality and Quantized Magnetoelectric Effect
• Topological chiral magnonic edge mode in a magnonic crystal
• Topological Magnon Insulator in Insulating Ferromagnet
• Spontaneous Magnon Decays
• Topological Phases of Sound and Light
• A Realization of the Haldane-Kane-Mele Model in a System of Localized Spins
• Weyl magnons in breathing pyrochlore antiferromagnets
• Hall effect of triplons in a dimerized quantum magnet
• Topological Triplon Modes and Bound States in a Shastry-Sutherland Magnet
• Kibble-Zurek mechanism in topologically non-trivial zigzag chains of polariton micropillars
• Damped Topological Magnons in the Kagomé-Lattice Ferromagnets
• Interacting quantum fluid in a polariton topological insulator
• Quantum Fluctuations and Excitations in Antiferromagnetic Quasicrystals
• Magnetic properties of the S=1/2 quasi-one-dimensional antiferromagnet CaCu2O3
• Uniform and staggered magnetizations induced by Dzyaloshinskii-Moriya interactions in isolated and coupled spin 1/2 dimers in a magnetic field
• The effect of Dzyaloshinskii-Moriya interactions on the phase diagram and magnetic excitations of SrCu2(BO3)2
• Magnetic chern bands and triplon Hall effect in an extended Shastry-Sutherland model
• Topological Paramagnetism in Frustrated Spin-One Mott Insulators
• Excitations and Quantum Fluctuations in Site Diluted Two-Dimensional Antiferromagnets
• Non-linear bond-operator theory and 1/d expansion for coupled-dimer magnets I: Paramagnetic phase
• Non-linear bond-operator theory and 1/d expansion for coupled-dimer magnets II: Antiferromagnetic phase and quantum phase transition
• A modified triplet-wave expansion method applied to the alternating Heisenberg chain
• Minimal model for the frustrated spin ladder system BiCu${}_2$PO${}_6$

Cited by in corpus (20)

• Topological excitations in the ferromagnetic Kitaev-Heisenberg model
• Non-Hermiticity and topological invariants of magnon Bogoliubov-de Gennes systems
• Topological magnon bands for magnonics
• Topological magnetic excitations
• Nontrivial Triplon Topology and Triplon Liquid in Kitaev-Heisenberg-type Excitonic Magnets
• Generalized Berry phase for a bosonic Bogoliubov system with exceptional points
• Triplon band splitting and topologically protected edge states in the dimerized antiferromagnet
• ${\mathbb{Z}}_2$ topological quantum paramagnet on a honeycomb bilayer
• Dirac surface states in magnonic analogs of topological crystalline insulators
• Magnonic Floquet Quantum Spin Hall Insulator in Bilayer Collinear Antiferromagnets
• Non-trivial topology of the quasi-one-dimensional triplons in the quantum antiferromagnet ${\text{BiCu}}_2{\text{PO}}_6$
• Dirac cones and mass terms in bosonic spectra
• Dirac Hamiltonians for bosonic spectra
• Detecting End-States of Topological Quantum Paramagnets via Spin Hall Noise Spectroscopy
• Delocalization of edge states in topological phases
• Kitaev-Heisenberg model on the star lattice: From chiral Majorana fermions to chiral triplons
• Higher-order topology and corner triplon excitations in two-dimensional quantum spin-dimer models
• Thermal Hall conductivity of a valence bond solid phase in the square lattice $J_1$-$J_2$ antiferromagnet Heisenberg model with a Dzyaloshinskii-Moriya interaction
• Topological excitations in quasi two-dimensional quantum magnets with weak interlayer interactions
• Fate of Bosonic Topological Edge Modes in the Presence of Many-Body Interactions