Spin correlations in an isotropic spin-5/2 two-dimensional antiferromagnet

Abstract

We report a neutron scattering study of the spin correlations for the spin 5/2, two-dimensional antiferromagnet Rb_2MnF_4 in an external magnetic field. Choosing fields near the system's bicritical point, we tune the effective anisotropy in the spin interaction to zero, constructing an ideal S=5/2 Heisenberg system. The correlation length and structure factor amplitude are closely described by the semiclassical theory of Cuccoli et al. over a broad temperature range but show no indication of approaching the low-temperature renormalized classical regime of the quantum non-linear sigma model.

4 pages, 3 EPS figures

References in corpus (2)

• The Square-Lattice Heisenberg Antiferromagnet at Very Large Correlation Lengths
• Spin Correlations in the Two-Dimensional Spin-5/2 Heisenberg Antiferromagnet Rb2MnF4

Cited by in corpus (7)

• Instantaneous Spin Correlations in La2CuO4
• Two-magnon excitations observed by neutron scattering in the two-dimensional spin-5/2 Heisenberg antiferromagnet Rb2MnF4
• Neutron Scattering study of Sr_2Cu_3O_4Cl_2
• Spin dynamics and magnetic correlation length in two-dimensional quantum Heisenberg antiferromagnets
• Neutron spin-echo study of the critical dynamics of spin-5/2 antiferromagnets in two and three dimensions
• Scaling relations in quasi-two-dimensional Heisenberg antiferromagnet
• Honeycomb-lattice Gamma model in a magnetic field: hidden Néel order and spin-flop transition