Thermodynamic properties of the anisotropic frustrated spin-chain compound linarite PbCuSO4(OH)2

We present a comprehensive macroscopic thermodynamic study of the quasi-one-dimensional (1D) s = 1/2 frustrated spin-chain system linarite. Susceptibility, magnetization, specific heat, magnetocaloric effect, magnetostriction, and thermal-expansion measurements were performed to characterize the magnetic phase diagram. In particular, for magnetic fields along the b axis five different magnetic regions have been detected, some of them exhibiting short-range-order effects. The experimental magnetic entropy and magnetization are compared to a theoretical modeling of these quantities using density matrix renormalization group (DMRG) and transfer matrix renormalization group (TMRG) approaches. Within the framework of a purely 1D isotropic model Hamiltonian, only a qualitative agreement between theory and the experimental data can be achieved. Instead, it is demonstrated that a significant symmetric anisotropic exchange of about 10% is necessary to account for the basic experimental observations, including the three-dimensional (3D) saturation field, and which in turn might stabilize a triatic (three-magnon) multipolar phase. © 2013, American Physical Society.

Keywords

Magnetic properties, Magnetism, Energy levels, Antiferromagnetism, Spin

Citation

Schäpers, M., Wolter, A. U. B., Drechsler, S. L., Nishimoto, S., Müller, K. H., Abdel-Hafiez, MSchottenhamel, W., Büchner, B., Richter, J., Ouladdiaf, B., Uhlarz, M., Beyer, R., Skourski, Y., Wosnitza, J., Rule, K. C., Ryll, H., Klemke, B., Kiefer, K., Reehuis, M., Willenberg, B., & Süllow, S. (2013). Thermodynamic properties of the anisotropic frustrated spin-chain compound linarite PbCuSO4(OH)2. Physical Review B, 88(18), 184410. doi:10.1103/PhysRevB.88.184410