论文标题
交替的铁抗磁性海森堡链的有限温度特性
Finite temperature properties of alternating ferro-antiferromagnetic Heisenberg chains
论文作者
论文摘要
我们提出了一项针对交替的铁磁交换的Spin-1/2海森堡链的研究，重点是交换耦合涵盖，二聚体和Haldane极限的作用。通过摄动理论和量子蒙特卡洛模拟的互补组合，我们报告了磁敏感性的结果以及在广泛的耦合常数以及不同温度上提取自旋间隙的结果。对于小铁磁耦合，我们发现摄动理论与量子蒙特卡洛之间有很好的一致性。对于任意交换耦合，我们表明，从量子蒙特卡洛获得的动态结构因子在三位链和霍尔丹链链频谱之间尺度。最后，我们将旋转差距的发现与与现有文献的交换耦合相比。
We present a study of the spin-1/2 Heisenberg chain with alternating ferro- and antiferromagnetic exchange, focusing on the role of the exchange couplings to cover both, dimer and Haldane limit. Employing a complementary combination of perturbation theory and quantum Monte Carlo simulation, we report results for the magnetic susceptibility as well as the dynamic structure factor over a wide range of coupling constants and for different temperatures to extract the spin gap. For a small ferromagnetic coupling, we find good agreement between perturbation theory and quantum Monte Carlo. For arbitrary exchange couplings we show that the dynamic structure factor, obtained from quantum Monte Carlo, scales between triplons and a Haldane chain spectrum. Finally, we contrast our findings for the spin gap versus the exchange couplings against existing literature.
