Non-magnetic ion site disorder effects on the quantum magnetism of a spin-1/2 equilateral triangular lattice antiferromagnet

Abstract

With the motivation to study how non-magnetic ion site disorder affects the quantum magnetism of Ba3CoSb2O9, a spin-1/2 equilateral triangular lattice antiferromagnet, we performed DC and AC susceptibility, specific heat, elastic and inelastic neutron scattering measurements on single crystalline samples of Ba2.87Sr0.13CoSb2O9 with Sr doping on non-magnetic Ba2+ ion sites. The results show that Ba2.87Sr0.13CoSb2O9 exhibits (i) a two-step magnetic transition at 2.7 K and 3.3 K, respectively; (ii) a possible canted 120-degree spin structure at zero field with reduced ordered moment as 1.24μB/Co; (iii) a series of spin state transitions for both H // ab-plane and H // c-axis. For H // ab-plane, the magnetization plateau feature related to the up-up-down phase is significantly suppressed; (iv) an inelastic neutron scattering spectrum with only one gapped mode at zero field, which splits to one gapless and one gapped mode at 9 T. All these features are distinctly different from those observed for the parent compound Ba3CoSb2O9, which demonstrates that the non-magnetic ion site disorder (the Sr doping) plays a complex role on the magnetic properties beyond the conventionally expected randomization of the exchange interactions. We propose the additional effects including the enhancement of quantum spin fluctuations and introduction of a possible spatial anisotropy through the local structural distortions.

arXiv comment10 pages, 10 figures

References in corpus (55)

• Continuous excitations of the triangular-lattice quantum spin liquid YbMgGaO4
• Rare-earth triangular lattice spin liquid: a single-crystal study of YbMgGaO${}_4$
• Evidence for a spinon Fermi surface in a triangular lattice quantum spin liquid candidate
• Gapless quantum spin liquid ground state in the two-dimensional spin-1/2 triangular antiferromagnet YbMgGaO${}_4$
• Experimental Realization of Spin-1/2 Triangular-Lattice Heisenberg Antiferromagnet
• Spin liquid nature in the Heisenberg $J_1$-$J_2$ triangular antiferromagnet
• Spin liquid phase of the $S=\frac{1}{2}$ $J_1-J_2$ Heisenberg model on the triangular lattice
• Disorder-Induced Mimicry of a Spin Liquid in YbMgGaO${}_4$
• Magnetization Process and Collective Excitations in the S=1/2 Triangular-Lattice Heisenberg Antiferromagnet Ba3CoSb2O9
• $\mu$SR evidence for the U(1) quantum spin liquid ground state in the triangular antiferromagnet YbMgGaO${}_4$
• Competing Spin Liquid States in the Spin-$1/2$ Heisenberg Model On Triangular Lattice
• Valence Bonds in Random Quantum Magnets: Theory and Application to YbMgGaO4
• Crystalline Electric Field Randomness in the Triangular Lattice Spin-Liquid YbMgGaO${}_4$
• Quantum Phase Diagram of the Triangular-Lattice XXZ Model in a Magnetic Field
• Spin-glass ground state in a triangular-lattice compound YbZnGaO${}_4$
• Topography of Spin Liquids on a Triangular Lattice
• Gapless spin-liquid phase in an extended spin 1/2 triangular Heisenberg model
• Absence of magnetic thermal conductivity in the quantum spin liquid candidate YbMgGaO4
• Quantum spin-liquid behavior in the spin-1/2 random Heisenberg antiferromagnet on the triangular lattice
• Scaling and data collapse from local moments in frustrated disordered quantum spin systems
• Static and Dynamical Properties of the Spin-1/2 Equilateral Triangular-Lattice Antiferromagnet Ba${}_3$CoSb${}_2$O${}_9$
• Dynamical structure factor of triangular-lattice antiferromagnet
• Static and dynamical spin correlations of the S=1/2 random-bond antiferromagnetic Heisenberg model on the triangular and the kagome lattices
• Microscopic Model Calculations for the Magnetization Process of Layered Triangular-Lattice Quantum Antiferromagnets
• Quasiclassical magnetic order and its loss in a spin-1/2 Heisenberg antiferromagnet on a triangular lattice with competing bonds
• Quantum phase diagram of the $S=1/2$ triangular-lattice antiferromagnet Ba${}_3$CoSb${}_2$O${}_9$
• Quantum spin-liquid behavior in the spin-1/2 random-bond Heisenberg antiferromagnet on the kagome lattice
• Strong quantum interactions prevent quasiparticle decay
• Nearest-neighbor resonating valence bonds in YbMgGaO4
• Symmetry fractionalization in the topological phase of the spin-$\frac{1}{2}$ $J_1$-$J_2$ triangular Heisenberg model
• Fractionalized excitations in the partially magnetized spin liquid candidate YbMgGaO4
• Magnetic Phase Diagram of the S=1/2 Triangular-Lattice Heisenberg Antiferromagnet Ba3CoNb2O9
• Nature of the randomness-induced quantum spin liquids in two dimensions
• Ground-state phase diagram of an anisotropic spin-$1/2$ model on the triangular lattice
• Random-Singlet Phase in Disordered Two-Dimensional Quantum Magnets
• Ground States of Spin-1/2 Triangular Antiferromagnets in a Magnetic Field
• Rearrangement of uncorrelated valence bonds evidenced by low-energy spin excitations in YbMgGaO4
• Survival of itinerant excitations and quantum spin state transitions in YbMgGaO${}_4$ with chemical disorder
• Avoided quasiparticle decay and enhanced excitation continuum in the spin-1/2 near-Heisenberg triangular antiferromagnet Ba3CoSb2O9
• Randomness-induced quantum spin liquid behavior in the $s=\frac{1}{2}$ random $J_1$-$J_2$ Heisenberg antiferromagnet on the square lattice
• Randomness-induced quantum spin liquid behavior in the s=1/2 random J1-J2 Heisenberg antiferromagnet on the honeycomb lattice
• Magnons and Excitation Continuum in XXZ triangular antiferromagnetic model: Application to $B{a}_{3}CoS{b}_2{O}_9$
• Randomness-induced quantum spin liquid behavior in the $s=$1/2 bond-random Heisenberg antiferromagnet on the pyrochlore lattice
• Phases of triangular lattice antiferromagnet near saturation
• Randomness induced spin-liquid-like phase in the spin-$1/2$ $J_1-J_2$ triangular Heisenberg model
• Finite-temperature behavior of a classical spin-orbit-coupled model for ${\text{YbMgGaO}}_4$ with and without bond disorder
• Lattice distortion effects on the frustrated spin-1 triangular-antiferromagnet A3NiNb2O9 (A = Ba, Sr and Ca)
• Signatures of a spin-1/2 cooperative paramagnet in the diluted triangular lattice of Y${}_2$CuTiO${}_6$
• Order by quenched disorder in the model triangular antiferromagnet RbFe(MoO4)2
• Extreme Suppression of Antiferromagnetic Order and Critical Scaling in a Two-Dimensional Random Quantum Magnet
• Observation of a random singlet state in a diluted Kitaev honeycomb material
• Field-induced decays in $XXZ$ triangular-lattice antiferromagnets
• Absence of moment fragmentation in the mixed $B$-site pyrochlore Nd${}_2$GaSbO${}_7$
• Random singlet state in Ba${}_5$CuIr${}_3$O${}_{12}$ single crystals
• Freezing of a disorder induced quantum spin liquid

Cited by in corpus (2)

• Modified large-$N$ approach to gapless spin liquids, magnetic orders, and dynamics: Application to triangular lattice antiferromagnets
• Anomalous enhancement of magnetism by nonmagnetic doping in the honeycomb-lattice antiferromagnet ErOCl