Quantum corrections to the spin-wave spectrum of La${}_2$CuO${}_4$ in an external magnetic field

Abstract

The effects of quantum fluctuations on the magnetic field dependence of the spin-wave gaps in the lamellar antiferromagnet La${}_2$CuO${}_4$ are considered. Nonlinear corrections to the spin-wave spectrum are calculated to leading order in 1/S, where $S$ is the localized spin. The nearest-neighbor exchange interactions between the Cu spins as well as the Dzyaloshinskii-Moriya interactions are taken into account. Using the experimental values of the components of the $g$-factor tensor, we get a satisfactory agreement with the experimental results for the field dependence of the gaps by Gozar {\it et al.} [Phys. Rev. Lett. {\bf 93}, 027001 (2004)], and obtain consistent values of the in-plane and inter-plane coupling constants. The field dependence of the dispersion of spin waves propagating perpendicular to the CuO${}_2$ planes is also discussed.

References in corpus (4)

• Crystal structure and high-field magnetism of La2CuO4
• Field dependence of the magnetic spectrum in anisotropic and Dzyaloshinskii-Moriya antiferromagnets: I. Theory
• Field dependence of the magnetic spectrum in anisotropic and Dzyaloshinskii-Moriya antiferromagnets: II. Raman spectroscopy
• Spin-flop transitions and spin-wave gaps in La_2CuO_4