Ground states of a frustrated spin-1/2 antifferomagnet: Cs_2CuCl_4 in a magnetic field

Abstract

We present detailed calculations of the magnetic ground state properties of Cs${}_2$CuCl${}_4$ in an applied magnetic field, and compare our results with recent experiments. The material is described by a spin Hamiltonian, determined with precision in high field measurements, in which the main interaction is antiferromagnetic Heisenberg exchange between neighboring spins on an anisotropic triangular lattice. An additional, weak Dzyaloshinkii-Moriya interaction introduces easy-plane anisotropy, so that behavior is different for transverse and longitudinal field directions. We determine the phase diagram as a function of field strength for both field directions at zero temperature, using a classical approximation as a first step. Building on this, we calculate the effect of quantum fluctuations on the ordering wavevector and components of the ordered moments, using both linear spinwave theory and a mapping to a Bose gas which gives exact results when the magnetization is almost saturated. Many aspects of the experimental data are well accounted for by this approach.

arXiv comment13 Pages, 9 Figures

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Cited by in corpus (39)

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• Extreme sensitivity of a frustrated quantum magnet: Cs_2CuCl_4
• Quantum stabilization of 1/3-magnetization plateau in Cs_2CuBr_4
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• Magnetic phase transitions in the two-dimensional frustrated quantum antiferromagnet Cs2CuCl4
• Magnetic vortex crystals in frustrated Mott insulator
• Magnetic phase diagram of the spin-1/2 antiferromagnetic zigzag ladder
• Deformed triangular lattice antiferromagnets in a magnetic field: role of spatial anisotropy and Dzyaloshinskii-Moriya interactions
• Algebraic vortex liquid in spin-1/2 triangular antiferromagnets: Scenario for Cs_2CuCl_4
• Ordering in Cs2CuCl4: Is there a proximate spin liquid?
• Avoided quasiparticle decay and enhanced excitation continuum in the spin-1/2 near-Heisenberg triangular antiferromagnet Ba3CoSb2O9
• Frustrated local moment models for Fe-pnictide magnetism
• Novel phases in a square-lattice frustrated ferromagnet : 1/3-magnetisation plateau, helicoidal spin-liquid and vortex crystal
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• Excitation spectra and ground state properties of the layered spin-1/2 frustrated antiferromagnets Cs_2CuCl_4 and Cs_2CuBr_4
• Effects of an external magnetic field on the gaps and quantum corrections in an ordered Heisenberg antiferromagnet with Dzyaloshinskii-Moriya anisotropy
• Half-magnetization plateau in a Heisenberg antiferromagnet on a triangular lattice
• Quasiparticles of spatially anisotropic triangular antiferromagnets in a magnetic field
• Elastic constants and ultrasonic attenuation in the cone state of the frustrated antiferromagnet Cs_2CuCl_4
• Quantum fluctuations in anisotropic triangular lattices with ferro- and antiferromagnetic exchange
• Low-temperature ordered phases of the spin-$\frac{1}{2}$ XXZ chain system Cs${}_2$CoCl${}_4$
• Magnetic properties of a metal-organic antiferromagnet on a distorted honeycomb lattice
• Nature of the low energy excitations in the short range ordered region of Cs${}_2$CuCl${}_4$ as revealed by ${}^{133}$Cs NMR
• Magnetic phase diagram slightly below the saturation field in the stacked $J_1$-$J_2$ model in the square lattice with the $J_{\text{C}}$ interlayer coupling
• Hard-core boson approach to the spin-1/2 triangular-lattice antiferromagnet Cs${}_2$CuCl${}_4$ at finite temperatures in magnetic fields higher than the saturation field
• Commensurate and incommensurate ground states of Cs_2CuCl_4 in a magnetic field
• Spin-liquid phase and order-by-disorder of classical Heisenberg spins on the swedenborgite lattice
• Anyonic Liquids in Nearly Saturated Spin Chains
• Bose-Einstein condensation of magnons in Cs${}_2$CuCl${}_4$: a dilute gas limit near the saturation magnetic field
• Magnetic Catalysis in Antiferromagnetic Films
• Two Coupled Chains are Simpler than One: Field-induced Chirality in a Frustrated Quantum Spin Ladder
• Effects of magnon-magnon interactions in a noncollinear magnet induced by combination of a symmetric and an antisymmetric exchange interaction
• Stabilizing the spiral order with spin-orbit coupling in an anisotropic triangular antiferromagnet
• Square-Lattice Antiferromagnet Subjected to a Magnetic Field Aligned with the Order Parameter