arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1601.07069cond-mat.str-el
收藏

强在位自旋轨道耦合系统中的Jahn-Teller效应

Jahn-Teller effect in systems with strong on-site spin-orbit coupling

Ekaterina M. Plotnikova, Maria Daghofer, Jeroen van den Brink, Krzysztof Wohlfeld

摘要:

当强的自旋轨道耦合消除轨道简并时,它同时似乎使Jahn-Teller机制无效。我们讨论了这样一种情况,t_2g流形的虹彩,并表明,虽然Jahn-Teller效应确实不影响的j_eff=1/2反铁磁有序基态,它会导致独特的签名,在j_eff=3/2自旋轨道激子。它允许自旋-轨道激子在最近的相邻位置之间跳跃,而不会在j_eff=1/2反铁磁体中产生缺陷。这是因为晶格驱动的Jahn-Teller机制只耦合到轨道自由度,但对定义同位旋j_z的波函数的相位不敏感。这与纯电子传播形成鲜明对比,它保存了同位旋,和Jahn-Teller耦合的存在下,可以解释测量的共振非弹性X射线散射光谱的Sr_2IrO_4的一些奇特的功能。

英文摘要:

When strong spin-orbit coupling removes orbital degeneracy, it would at the same time appear to render the Jahn-Teller mechanism ineffective. We discuss such a situation, the t_2g manifold of iridates, and show that, while the Jahn-Teller effect does indeed not affect the j_eff=1/2 antiferromagnetically ordered ground state, it leads to distinctive signatures in the j_eff=3/2 spin-orbit exciton. It allows for a hopping of the spin-orbit exciton between the nearest neighbor sites without producing defects in the j_eff=1/2 antiferromagnet. This arises because the lattice-driven Jahn-Teller mechanism only couples to the orbital degree of freedom, but is not sensitive to the phase of the wave function that defines isospin j_z. This contrasts sharply with purely electronic propagation, which conserves isospin, and presence of Jahn-Teller coupling can explain some of the peculiar features of measured resonant inelastic x-ray scattering spectra of Sr_2IrO_4.

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。

↑