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arXiv 1406.5136cond-mat.str-el
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等电子调谐铁磷族化合物模型中的磁和伊辛量子相变

Magnetic and Ising quantum phase transitions in a model for isoelectronically tuned iron pnictides

Jianda Wu, Qimiao Si, Elihu Abrahams

摘要:

对坏金属行为的考虑导致了早期提出的在P下的量子临界点,因为在铁磷属元素化物中掺杂As,这已经被实验观察到。在这里,我们研究了一个有效的模型等电子调谐pnictides使用大- $N$的方法。该模型包含反铁磁和伊辛-伊辛序参量适用于$J_1$ - $J_2$交换耦合的本地力矩的Fe正方形晶格,和阻尼所造成的相干巡回电子。零温磁转变和伊辛转变是同时发生的,并且基本上是连续的。序参数的跳跃非常小,并进一步减少了平面间的耦合,量子临界因此发生在一个很宽的动力学范围。我们的研究结果为进一步研究磷掺杂砷化铁的量子临界性质提供了基础。

英文摘要:

Considerations of the bad-metal behavior led to an early proposal for a quantum critical point under a P for As doping in the iron pnictides, which has since been experimentally observed. We study here an effective model for the isoelectronically tuned pnictides using a large-$N$ approach. The model contains antiferromagnetic and Ising-nematic order parameters appropriate for $J_1$-$J_2$ exchange-coupled local moments on an Fe square lattice, and a damping caused by coherent itinerant electrons. The zero-temperature magnetic and Ising transitions are concurrent and essentially continuous. The order-parameter jumps are very small, and are further reduced by the inter-plane coupling; quantum criticality hence occurs over a wide dynamical range. Our results provide the basis for further studies on the quantum critical properties in the P-doped iron arsenides.

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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