Analysis of the finite-temperature phase transition of Heisenberg antiferromagnetic compound LiVGe2O6

作者：Huang Hai; Li Wei-Feng^*

来源：Acta Physica Sinica, 2013, 62(21): 217501.

DOI：10.7498/aps.62.217501

• Heisenberg model
• O(3) non-linear sigma model
• finite-temperature phase transition

The susceptibility and nuclear magnetic resonance measurements on quasi-one-dimensional spin-1 Heisenberg antiferromagnet LiVGe2O6 indicate that this material shows a phase transition from paramagnetic state to antiferromagnetic Neel state at about 22 K, and there exists a gap in the low-temperature magnetic excitation spectrum. Based on the model Hamiltonian of LiVGe2O6, we propose a low-energy field theory-Ginzburg-Landau theory for this compound. From this theory, we study the finite-temperature phase transition induced by spontaneous symmetry breaking and then calculate the finite-temperature susceptibility of LiVGe2O6. All the theoretical calculations are consistent with the experimental results.

• 出版日期2013-11
• 单位华北电力大学; 华北电力大学（保定）