Highly dispersive magnons with spin-gap like features in the frustrated ferromagnetic S=1/2 chain compound Ca2Y2Cu5O10 detected by inelastic neutron scattering

Abstract

We report inelastic neutron scattering experiments in Ca2Y2Cu5O10 and map out the full one magnon dispersion which extends up to a record value of 53 meV for frustrated ferromagnetic (FM) edge-sharing CuO2 chain (FFESC) cuprates. A homogeneous spin-1/2 chain model with a FM nearest-neighbor (NN), an antiferromagnetic (AFM) next-nearest-neighbor (NNN) inchain, and two diagonal AFM interchain couplings (ICs) analyzed within linear spin-wave theory (LSWT) reproduces well the observed strong dispersion along the chains and a weak one perpendicularly. The ratio R=|J_{a2}/J_{a1}| of the FM NN and the AFM NNN couplings is found as ~0.23, close to the critical point Rc=1/4 which separates ferromagnetically and antiferromagnetically correlated spiral magnetic ground states in single chains, whereas Rc>0.25 for coupled chains is considerably upshifted even for relatively weak IC. Although the measured dispersion can be described by homogeneous LSWT, the scattering intensity appears to be considerably reduced at ~11.5 and ~28 meV. The gap-like feature at 11.5 meV is attributed to magnon-phonon coupling whereas based on DMRG simulations of the dynamical structure factor the gap at 28 meV is considered to stem partly from quantum effects due to the AFM IC. Another contribution is ascribed to the intrinsic superstructure from the distorting incommensurate pattern of CaY cationic chains adjacent to the CuO2 ones. It gives rise to non-equivalent CuO4 units and Cu-O-Cu bond angles Phi and a resulting distribution of all exchange integrals. The J's fitted by homogeneous LSWT are regarded as average values. The record value of the FM NN integral J1=24 meV among FFESC cuprates can be explained by a non-universal Phi (not 90 deg.) and Cu-O bond length dependent anisotropic mean direct FM Cu-O exchange K_{pd}~120 meV. Enhanced K_{pd} values are also needed to compensate a significant AFM J_{dd} > ~6 meV.

arXiv comment36 pages

References in corpus (54)

• Dynamical density-matrix renormalization-group method
• Electronic States and Magnetic Propertis of Edge-sharing Cu-O Chains
• Emergent multipolar spin correlations in a fluctuating spiral - The frustrated ferromagnetic S=1/2 Heisenberg chain in a magnetic field
• Numerical and approximate analytical results for the frustrated spin-1/2 quantum spin chain
• Frustrated ferromagnetic spin-1/2 chain in a magnetic field: The phase diagram and thermodynamic properties
• NMR and LDA evidence for spiral magnetic order in the chain cuprate LiCu2O2
• Spinons in the strongly correlated copper oxide chains in SrCuO2
• The Role of Lattice Coupling in Establishing Electronic and Magnetic Properties in Quasi-One-Dimensional Cuprates
• Quantum spin liquid in frustrated one dimensional LiCuSbO4
• Tenth-order high-temperature expansion for the susceptibility and the specific heat of spin-s Heisenberg models with arbitrary exchange patterns: Application to pyrochlore and kagome magnets
• Eighth-order high-temperature expansion for general Heisenberg Hamiltonians
• Zigzag spin chains with antiferromagnetic-ferromagnetic interactions: Transfer-matrix renormalization group study
• Thermodynamics of multiferroic spin chains
• Anisotropic Superexchange for nearest and next nearest coppers in chain, ladder and lamellar cuprates
• Electron-lattice interactions strongly renormalize the charge transfer energy in the spin-chain cuprate Li${}_2$CuO${}_2$
• Determining the Short-Range Spin Correlations in Cuprate Chain Materials with Resonant Inelastic X-ray Scattering
• Intertwined nematic orders in a frustrated ferromagnet
• On the absence of a spiral magnetic order in Li2CuO2 with one-dimensional CuO2 ribbon chains
• Highly Dispersive Spin Excitations in the Chain Cuprate Li2CuO2
• The spin gap in malachite Cu2(OH)2CO3 and its evolution under pressure
• Multipolar, magnetic and vibrational lattice dynamics in the low temperature phase of uranium dioxide
• Thermodynamics of a one-dimensional frustrated spin-1/2 Heisenberg ferromagnet
• Microscopic magnetic modeling for the $S$=1/2 alternating chain compounds Na${}_3$Cu${}_2$SbO${}_6$ and Na${}_2$Cu${}_2$TeO${}_6$
• Saturation field of frustrated chain cuprates: broad regions of predominant interchain coupling
• Anisotropic superexchange of a 90 degree Cu-O-Cu bond
• Magnetic Excitations of Spin-Gap System Na3Cu2SbO6 with Distorted Honeycomb Structure
• A Panoply of Orders from a Quantum Lifshitz Field Theory
• Temperature dependent optical conductivity of undoped cuprates with weak exchange
• Evidence for a magnetic field-induced unconventional nematic state in the frustrated and anisotropic spin-chain cuprate LiCuSbO${}_4$
• NaCuMoO_4(OH) as a Candidate Frustrated J_1-J_2 Chain Quantum Magnet
• Femtosecond dynamics of magnetic excitations from resonant inelastic x-ray scattering in CaCu2O3
• Large quantum fluctuations in the strongly coupled spin-1/2 chains of green dioptase: a hidden message from birds and trees
• Static and Dynamic Magnetic Response of Fragmented Haldane-like Spin Chains in Layered Li3Cu2SbO6
• The strength of frustration and quantum fluctuations in LiVCuO4
• Neutron Scattering study of Sr_2Cu_3O_4Cl_2
• Magnetic structure of the edge-sharing copper oxide chain compound NaCu2O2
• Ca2Y2Cu5O10: the first frustrated quasi-1D ferromagnet close to criticality
• Investigation of the presence of charge order in magnetite by measurement of the spin wave spectrum
• Magnetism of sodium superoxide
• Heisenberg exchange parameters of molecular magnets from the high-temperature susceptibility expansion
• Characterization of the Spin-1/2 Linear-Chain Ferromagnet CuAs${}_2$O${}_4$
• The dynamics of linarite: Observations of magnetic excitations
• Coexistence of valence-bond formation and topological order in the Frustrated Ferromagnetic $J_1$-$J_2$ Chain
• Single-crystal growth and dependences on the hole concentration and magnetic field of the magnetic ground state in the edge-sharing CuO${}_2$ chain system Ca${}_{2+x}$Y${}_{2-x}$Cu${}_5$O${}_{10}$
• Cross-over from an incommensurate singlet spiral state with a vanishingly small spin-gap to a valence bond solid state in dimerized frustrated ferromagnetic spin-chains
• Possible quadrupolar nematic phase in the frustrated spin chain LiCuSbO${}_4$: an NMR investigation
• Thermodynamics of frustrated ferromagnetic spin-$1/2$ Heisenberg chains: The role of inter-chain coupling
• Effects of hole-doping on the magnetic ground state and excitations in the edge-sharing CuO${}_2$ chains of Ca${}_{2+x}$Y${}_{2-x}$Cu${}_5$O${}_{10}$
• Two-magnon Raman scattering from the Cu3O4 layers in (Sr,Ba)2Cu3O4Cl2
• Comment on `Oxygen vacancy-induced magnetic moment in edge-sharing CuO${}_2$ chains of Li${}_2$CuO${}_2$'
• Magnetic excitations from the two-dimensional interpenetrating Cu framework in Ba${}_2$Cu${}_3$O${}_4$Cl${}_2$
• Fate of Quasiparticle at Mott Transition and Interplay with Lifshitz Transition Studied by Correlator Projection Method
• Electronic and magnetic excitations in the "half-stuffed" Cu--O planes of Ba${}_2$Cu${}_3$O${}_4$Cl${}_2$ measured by resonant inelastic x-ray scattering
• Spin dynamics of edge-sharing spin chains in SrCa13Cu24O41

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