ABSTRACT

The phase transitions, magnetic and thermodynamic properties of the three-dimensional antiferromagnetic Heisenberg model on a layered triangular lattice in a magnetic field are investigated employing the Monte Carlo method. The studies are carried out in the magnetic field range of 0 ≤ h ≤ 12. The magnetic structures of the ground state are obtained in a wide range of magnetic field values. The character of phase transitions is determined using the histogram method for data analysis. A second-order phase transition is found to occur in the range of 0 ≤ h ≤ 10. It is shown that a further increase in the magnetic field removes the degeneracy of the ground state and smears the phase transition.

摘要

使用蒙特卡罗方法研究了磁场中分层三角形晶格上三维反铁磁海森堡模型的相变、磁性和热力学性质。这些研究是在 0 ≤  h  ≤ 12 的磁场范围内进行的。基态的磁结构是在很宽的磁场值范围内获得的。使用直方图方法进行数据分析，确定相变的特征。发现在 0 ≤ h  ≤ 10的范围内发生了二阶相变 。结果表明，磁场的进一步增加消除了基态的简并性并涂抹了相变。