From deconfined spinons to coherent magnons in an antiferromagnetic Heisenberg chain with long range interactions
From deconfined spinons to coherent magnons in an antiferromagnetic Heisenberg chain with long range interactions
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DOI：
10.21468/scipostphys.10.5.110
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发表时间：
2020-05
期刊：
影响因子：
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通讯作者：
Luhang Yang;A. Feiguin
中科院分区：
文献类型：
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作者：
Luhang Yang;A. Feiguin
我们研究的频谱和性质的激发的反铁磁（AFM）海森堡链与交错的长程相互作用，无论是数值使用含时密度矩阵重整化群（tDMRG）方法和通过一个多自旋近似，定性地解释其主要特点。交换的未受挫折的长程性质有效地增加了系统的维度，并且链能够经历真正的对称性破缺并发展长程有序，从无间隙自旋液体过渡到无间隙有序AFM相。我们计算了动量分辨自旋动力学结构因子，发现对于弱衰减相互作用，尼尔序的出现可以与成为相干磁振子的自旋子束缚态的形成相关联。准粒子带从被推到更高能量的双自旋连续体中泄漏出来。我们的物理图像也支持的行为的激励的实时分析。
We study the spectrum and the nature of the excitations of an antiferromagnetic (AFM) Heisenberg chain with staggered long range interactions, both numerically using the time-dependent density matrix renormalization group (tDMRG) method and by means of a multi-spinon approximation that qualitatively explains its main features. The unfrustrated long-range nature of the exchange effectively increases the dimensionality of the system and the chain is able to undergo true symmetry breaking and develop long range order, transitioning from a gapless spin liquid to a gapless ordered AFM phase. We calculated the momentum resolved spin dynamical structure factor and found that for weakly decaying interactions the emergence of Neel order can be associated to the formation of bound states of spinons that become coherent magnons. The quasiparticle band leaks out from the two-spinon continuum that is pushed up to higher energies. Our physical picture is also supported by an analysis of the behavior of the excitations in real-time.