Department of Information Electronics, Fukuoka Institute of Technology, Fukuoka 811-0295, Japan.
J Phys Condens Matter. 2011 Mar 16;23(10):106001. doi: 10.1088/0953-8984/23/10/106001. Epub 2011 Feb 18.
The magnetism of Pd(1-x)Mn(x) is investigated theoretically. A localized spin model for Mn spins that interact with short-range antiferromagnetic interactions and long-range ferromagnetic interactions via itinerant d electrons is set up, with no adjustable parameters. A multicanonical Monte Carlo simulation, combined with a procedure of symmetry breaking, is employed to discriminate between the ferromagnetic and spin glass orders. The transition temperature and the low-temperature phase are determined from the temperature variation of the specific heat and the probability distributions of the ferromagnetic order parameter and the spin glass order parameter at different concentrations. The calculation results reveal that only the ferromagnetic phase exists at x < 0.02, that only the spin glass phase exists at x > 0.04, and that the two phases coexist at intermediate concentrations. This result agrees semi-quantitatively with experimental results.
我们对 Pd(1-x)Mn(x) 的磁性进行了理论研究。建立了一个局域自旋模型，用于 Mn 自旋，该模型通过巡游 d 电子与短程反铁磁相互作用和长程铁磁相互作用相互作用，没有可调参数。采用多正则蒙特卡罗模拟，结合对称破缺过程，来区分铁磁有序和自旋玻璃有序。通过比热随温度的变化以及不同浓度下铁磁有序参数和自旋玻璃有序参数的概率分布，确定了转变温度和低温相。计算结果表明，在 x < 0.02 时仅存在铁磁相，在 x > 0.04 时仅存在自旋玻璃相，而在中间浓度时则两相共存。这一结果与实验结果基本相符。
