Anomalous thermal broadening in the Shastry-Sutherland model and SrCu${}_2($BO${}_3{)}_2$

Abstract

The quantum magnet SrCu${}_2($BO${}_3{)}_2$ and its remarkably accurate theoretical description, the spin-$1/2$ Shastry-Sutherland model, host a variety of intriguing phenomena such as a dimer ground state with a nearly flat band of triplon excitations, a series of magnetization plateaux, and a possible pressure-induced deconfined quantum critical point. One open puzzle originating from inelastic neutron scattering and Raman experiments is the anomalous broadening of the triplon modes at relatively low temperatures compared to the triplon gap $\Delta$. We demonstrate that the experimentally observed broadening is captured by the Shastry-Sutherland model. To this end, we develop a numerical simulation method based on matrix-product states to simulate dynamical spectral functions at nonzero temperatures accurately. Perturbative calculations identify the origin of this phenomenon as a small energy scale compared to $\Delta$ between single triplon and bound triplon states at the experimentally relevant model parameters.

arXiv comment5 pages, 5 figures

References in corpus (59)

• Exact dimer ground state of the two dimensional Heisenberg spin system SrCu_2(BO_3)_2
• Magnetic Superstructure in the Two-Dimensional Quantum Antiferromagnet SrCu2(BO3)2
• Minimally Entangled Typical Thermal State Algorithms
• Minimally entangled typical quantum states at finite temperature
• Quantum Phase Transitions in the Shastry-Sutherland Model for $\mathbf{SrC}{\mathbf{u}}_2(\mathbf{B}{\mathbf{O}}_3{)}_2$
• Direct Evidence for the Localized Single-Triplet Excitations and the Dispersive Multi-Triplets Excitations in SrCu2(BO3)2
• Tensor network study of the Shastry-Sutherland model in zero magnetic field
• Magnetization of SrCu2(BO3)2 in ultrahigh magnetic fields up to 118 T
• Crystals of bound states in the magnetization plateaus of the Shastry-Sutherland model
• Magnetization plateaus of the Shastry-Sutherland model for SrCu_2(BO_3)_2: SDW, supersolid and bound states
• Hall effect of triplons in a dimerized quantum magnet
• Observation of a 4-spin Plaquette Singlet State in the Shastry-Sutherland compound SrCu2(BO3)2
• Magnetostriction and magnetic texture to 97.4 Tesla in frustrated SrCu2(BO3)2
• Dispersion and Symmetry of Bound States in the Shastry-Sutherland Model
• Direct observation of the multiple spin gap excitations in two-dimensional dimer system SrCu2(BO3)2
• A quantum magnetic analogue to the critical point of water
• Topological Triplon Modes and Bound States in a Shastry-Sutherland Magnet
• Mott insulating states with competing orders in the triangular lattice Hubbard model
• Dzyaloshinski-Moriya Interaction in the 2D Spin Gap System SrCu2(BO3)2
• Phase Diagram of the quadrumerized Shastry-Sutherland Model
• Various series expansions for a Heisenberg antiferromagnet model for SrCu${}_2$(BO${}_3$)${}_2$
• Magnetization plateaus as insulator-superfluid transitions in quantum spin systems
• Finite-temperature lineshapes in gapped quantum spin chains
• Fractalization drives crystalline states in a frustrated spin system
• Quantum Criticality and Spin Liquid Phase in the Shastry-Sutherland model
• Collective Singlet Excitations and Evolution of Raman Spectral Weights in the 2D Spin Dimer Compound SrCu2(BO3)2
• Progress on stochastic analytic continuation of quantum Monte Carlo data
• Incomplete devil's staircase in the magnetization curve of SrCu2(BO3)2
• Signatures of a Deconfined Phase Transition on the Shastry-Sutherland Lattice: Applications to Quantum Critical SrCu${}_2$(BO${}_3$)${}_2$
• High Resolution Study of Spin Excitations in the Shastry-Sutherland Singlet Ground State of SrCu2(BO3)2
• Stripes, Antiferromagnetism, and the Pseudogap in the Doped Hubbard Model at Finite Temperature
• Thermodynamic properties of the Shastry-Sutherland model throughout the dimer-product phase
• Field dependence of the quantum ground state in the Shastry-Sutherland system SrCu${}_2$(BO${}_3$)${}_2$
• Low-Lying Magnetic Excitation of the Shastry-Sutherland Model
• Competition between intermediate plaquette phases in SrCu${}_2$(BO${}_3$)${}_2$ under pressure
• Direct Observation of the Quantum Phase Transition of SrCu${}_2$(BO${}_3$)${}_2$ by High-Pressure and Terahertz Electron Spin Resonance
• A Novel Ordered Phase in SrCu2(BO3)2 under High Pressure
• Thermodynamic properties of the Shastry-Sutherland model from quantum Monte Carlo simulations
• The effect of Dzyaloshinskii-Moriya interactions on the phase diagram and magnetic excitations of SrCu2(BO3)2
• Dynamic Structure Factor of the Two-Dimensional Shastry-Sutherland Model
• Dynamics and Instabilities of the Shastry-Sutherland Model
• Tensor network study of the $m=1/2$ magnetization plateau in the Shastry-Sutherland model at finite temperature
• Far infrared study of the two dimensional dimer spin system SrCu_2(BO_3)_2
• Finite Temperature Dynamical Structure Factor of Alternating Heisenberg Chains
• Field-Induced Effects of Anisotropic Magnetic Interactions in SrCu2(BO3)2
• Continuous and Discontinuous Quantum Phase Transitions in a Model Two-Dimensional Magnet
• Unveiling new quantum phases in the Shastry-Sutherland compound SrCu2(BO3)2up to the saturation magnetic field
• Correlated decay of triplet excitations in the Shastry-Sutherland compound SrCu${}_2$(BO${}_3$)${}_2$
• SrCu${}_2$(BO${}_3$)${}_2$ under pressure: a first-principle study
• Magnetic excitations in the S = 1/2 antiferromagnetic-ferromagnetic chain compound BaCu2V2O8 at zero and finite temperature
• Field-induced bound-state condensation and spin-nematic phase in SrCu${}_2$(BO${}_3$)${}_2$ revealed by neutron scattering up to 25.9 T
• Symmetries and Triplet Dispersion in a Modified Shastry-Sutherland Model for SrCu_2(BO_3)_2
• Multi-triplet bound states and finite-temperature dynamics in highly frustrated quantum spin ladders
• Thermally populated versus field-induced triplon bound states in the Shastry-Sutherland lattice SrCu${}_2$(BO${}_3$)${}_2$
• Bose-Einstein condensation in honeycomb dimer magnets and $\mathrm{Y}{\mathrm{b}}_2\mathrm{S}{\mathrm{i}}_2{\mathrm{O}}_7$
• Time-dependent correlations in quantum magnets at finite temperature
• Tensor network study of the Shastry-Sutherland model with weak interlayer coupling
• Order, Disorder and Monopole Confinement in the Spin-$1/2$ XXZ Model on a Pyrochlore Tube
• Spectroscopy and complex-time correlations using minimally entangled typical thermal states

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