Commensurate and incommensurate ground states of Cs_2CuCl_4 in a magnetic field

Abstract

We present calculations of the magnetic ground state of Cs_2CuCl_4 in an applied magnetic field, with the aim of understanding the commensurately ordered state that has been discovered in recent experiments. This layered material is a realization of a Heisenberg antiferromagnet on an anisotropic triangular lattice. Its behavior in a magnetic field depends on field orientation, because of weak Dzyaloshinskii-Moriya interactions.We study the system by mapping the spin-1/2 Heisenberg Hamiltonian onto a Bose gas with hard core repulsion. This Bose gas is dilute, and calculations are controlled, close to the saturation field. We find a zero-temperature transition between incommensurate and commensurate phases as longitudinal field strength is varied, but only incommensurate order in a transverse field. Results for both field orientations are consistent with experiment.

5 Pages, 3 Figures

References in corpus (6)

• Bose-Einstein Condensation of Magnons in Cs2CuCl4
• Anomalous Excitation Spectra of Frustrated Quantum Antiferromagnets
• Algebraic vortex liquid in spin-1/2 triangular antiferromagnets: Scenario for Cs_2CuCl_4
• Ordering in Cs2CuCl4: Is there a proximate spin liquid?
• Ground states of a frustrated spin-1/2 antifferomagnet: Cs_2CuCl_4 in a magnetic field
• Spin dynamics of the quasi two dimensional spin-1/2 quantum magnet Cs_2CuCl_4

Cited by in corpus (9)

• Ordering in spatially anisotropic triangular antiferromagnets
• Extreme sensitivity of a frustrated quantum magnet: Cs_2CuCl_4
• Quantum stabilization of 1/3-magnetization plateau in Cs_2CuBr_4
• Half-magnetization plateau in a Heisenberg antiferromagnet on a triangular lattice
• Elastic constants and ultrasonic attenuation in the cone state of the frustrated antiferromagnet Cs_2CuCl_4
• Quasiparticles of spatially anisotropic triangular antiferromagnets in a magnetic field
• Variational Studies of Triangular Heisenberg Antiferromagnet in Magnetic Field
• Interplay of frustration and magnetic field in the two-dimensional quantum antiferromagnet Cu(tn)Cl${}_2$
• Supersolid phase of Three-dimensional spin and hardcore-boson models