Spin excitations in the two-dimensional strongly coupled dimer system malachite
arXiv:1412.5908 · doi:10.1103/PhysRevB.91.060402
Abstract
The mineral malachite, Cu2(OD)2CO3, has a quantum spin-liquid ground state and no long-range magnetic order down to at least T=0.4 K. Inelastic neutron scattering measurements show that the excitation spectrum consists of dispersive gapped singlet-triplet excitations, characteristic of spin-1/2 dimer-forming Heisenberg antiferromagnets. We identify a new two-dimensional dimerized coupling scheme with strong interdimer coupling J'/J1~0.3 that places malachite between strongly coupled alternating chains, square lattice antiferromagnets, and infinite-legged ladders. The geometry of the interaction scheme resembles the staggered dimer lattice, which may allow unconventional quantum criticality.
References in corpus (25)
- Restoring the density-gradient expansion for exchange in solids and surfaces
- Generalized gradient approximation for solids and their surfaces
- Anyons in an exactly solved model and beyond
- Mantid - Data Analysis and Visualization Package for Neutron Scattering and Experiments
- "Deconfined" quantum critical points
- Bose-Einstein Condensation in Magnetic Insulators
- Thermodynamics of Spin S = 1/2 Antiferromagnetic Uniform and Alternating-Exchange Heisenberg Chains
- Dynamics of a two-dimensional quantum spin liquid: signatures of emergent Majorana fermions and fluxes
- Spin Liquid Ground State of the Spin-1/2 Square - Heisenberg Model
- Crystals of bound states in the magnetization plateaus of the Shastry-Sutherland model
- Evidence of Unconventional Universality Class in a Two-Dimensional Dimerized Quantum Heisenberg Model
- Comprehensive quantum Monte Carlo study of the quantum critical points in planar dimerized/quadrumerized Heisenberg models
- Low-Lying Magnetic Excitation of the Shastry-Sutherland Model
- Frustrated 3-Dimensional Quantum Spin Liquid in CuHpCl
- The spin gap in malachite Cu2(OH)2CO3 and its evolution under pressure
- Quantum Statistics of Interacting Dimer Spin Systems
- Two-particle decay and quantum criticality in dimerized antiferromagnets
- Finite Temperature Dynamical Structure Factor of Alternating Heisenberg Chains
- On the dynamics of coupled S=1/2 antiferromagnetic zig-zag chains
- Spin-Peierls instability in a quantum spin chain with Dzyaloshinskii-Moriya interaction
- Asymmetric Thermal Lineshape Broadening in a Gapped 3-Dimensional Antiferromagnet - Evidence for Strong Correlations at Finite Temperature
- Finite Temperature Dynamics of the Spin 1/2 Bond Alternating Heisenberg Antiferromagnetic Chain
- Experimental evidence for a spin gap in the s=1/2 quantum antiferromagnet Cu(OH)CO
- Dynamical Structure Factors for Dimerized Spin Systems
- Vector boson excitations near deconfined quantum critical points