Effects of an external magnetic field on the gaps and quantum corrections in an ordered Heisenberg antiferromagnet with Dzyaloshinskii-Moriya anisotropy

Abstract

We study the effects of external magnetic field on the properties of an ordered Heisenberg antiferromagnet with the Dzyaloshinskii-Moriya (DM) interaction. Using the spin-wave theory quantum correction to the energy, on-site magnetization, and uniform magnetization are calculated as a function of the field H and the DM anisotropy constant D. It is shown that the spin-wave excitations exhibit an unusual field-evolution of the gaps. This leads to various non-analytic dependencies of the quantum corrections on H and D. It is also demonstrated that, quite generally, the DM interaction suppresses quantum fluctuations, thus driving the system to a more classical ground state. Most of the discussion is devoted to the spin-S, two-dimensional square lattice antiferromagnet, whose S=1/2 case is closely realized in K2V3O8 where at H=0 the DM anisotropy is hidden by the easy-axis anisotropy but is revealed in a finite field. The theoretical results for the field-dependence of the spin-excitation gaps in this material are presented and the implications for other systems are discussed.

arXiv comment15+ pages, 14 Figures

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Cited by in corpus (18)

• Anomalous thermal conductivity and magnetic torque response in the honeycomb magnet $\alpha$-RuCl${}_3$
• Damped Topological Magnons in the Kagomé-Lattice Ferromagnets
• Pseudospin-lattice coupling in the spin-orbit Mott insulator Sr2IrO4
• The Two-Dimensional Square-Lattice S=1/2 Antiferromagnet Cu(pz)${}_2$(ClO${}_4$)${}_2$
• Uniform and staggered magnetizations induced by Dzyaloshinskii-Moriya interactions in isolated and coupled spin 1/2 dimers in a magnetic field
• The effect of Dzyaloshinskii-Moriya interactions on the phase diagram and magnetic excitations of SrCu2(BO3)2
• Magneto-Dielectric Effect in the S = 1/2 Quasi-Two Dimensional Antiferromagnet K2V3O8
• Field dependence of the magnetic spectrum in anisotropic and Dzyaloshinskii-Moriya antiferromagnets: I. Theory
• Magnetic Excitation Spectrum of the Square Lattice S=1/2 Heisenberg Antiferromagnet K2V3O8
• Presaturation phase with no dipolar order in a quantum ferro-antiferromagnet
• Scaling behavior of the energy gap of spin-1/2 AF-Heisenberg chain in both uniform and staggered fields
• Hydrodynamic relation in 2D Heisenberg antiferromagnet in a field
• Magnon interactions in the quantum paramagnetic phase of CoNb${}_2$O${}_6$
• Coupling of spin and lattice modes in the S=1/2 two-dimensional antiferromagnet K${}_2$V${}_3$O${}_8$ with magneto-dielectric couplings
• Quantum corrections of the Dzyaloshinskii-Moriya interaction on the spin-1/2 AF-Heisenberg chain in an uniform magnetic field
• Magnetic Catalysis in Antiferromagnetic Films
• Two Coupled Chains are Simpler than One: Field-induced Chirality in a Frustrated Quantum Spin Ladder
• Temperature dependence of the $(\pi ,0)$ anomaly in the excitation spectrum of the 2D quantum Heisenberg antiferromagnet