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arXiv 0903.4408cond-mat.str-el
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铁磷属元素化合物的交换常数和中子能谱

Exchange Constants and Neutron Spectra of Iron Pnictide Materials

Rajiv R. P. Singh

摘要:

我们证明了Zhao等人(arXiv:0903.2686v1)在CaFe $_2$ As $_2$中观察到的中子散射谱和Han等人(Phys.Rev.Lett. 102,107003(2009)),可以通过假设这些材料中轨道顺序的作用来解释。我们写下一个简单的模型哈密顿与四角对称,其自旋波谱描述所观察到的色散关系。我们进一步认为,这些材料具有轨道选择性莫特转变,这是由相邻的铁原子之间的超交换驱动。我们认为,减少自旋和准一维,而不是挫折是负责减少这些材料的时刻。

英文摘要:

We show that the neutron scattering spectra observed in CaFe$_2$As$_2$ by Zhao et al (arXiv:0903.2686v1) and the highly unusual spatially anisotropic exchange constants in the iron pnictides derived by Han et al (Phys. Rev. Lett. 102, 107003 (2009)), using electronic structure calculations, can be explained by assuming a role for orbital order in these materials. We write down a simple model Hamiltonian with tertagonal symmetry, whose spin-wave spectra describes the observed dispersion relations. We further argue that these materials have orbital selective Mott transition, which is driven by superexchange between neighboring iron atoms. We suggest that reduced spin and quasi-one dimensionality and not frustration are responsible for the reduced moments in these materials.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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