Extreme tensile strain states in La0.7Ca0.3MnO3 membranes
Extreme tensile strain states in La0.7Ca0.3MnO3 membranes
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DOI：
10.1126/science.aax9753
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发表时间：
2020-04-03
期刊：
影响因子：
56.9
通讯作者：
Hwang, Harold Y.
中科院分区：
文献类型：
--
作者：
Hong, Seung Sae;Gu, Mingqiang;Hwang, Harold Y.
复杂氧化物中涌现现象的一个显著特征是基态之间的竞争与合作。在锰氧化物中，金属相和绝缘相之间的平衡可以通过晶格来调节;扩展晶格控制的范围将增强进入其他相的能力。我们稳定了纳米级La0.7Ca0.3MnO3膜的均匀极端拉伸应变，单轴超过8%，双轴超过5%。单轴和双轴应变在明显不同的应变值下抑制铁磁金属，诱导出可以被磁场熄灭的绝缘体。电子结构计算表明，该绝缘体由电荷有序的Mn ~（4+）和Mn ~（3+）组成，在平面内存在交错的应变增强Jahn-Teller畸变.这种高度可调的应变膜方法为设计和操纵相关电子态提供了广阔的机会。
A defining feature of emergent phenomena in complex oxides is the competition and cooperation between ground states. In manganites, the balance between metallic and insulating phases can be tuned by the lattice; extending the range of lattice control would enhance the ability to access other phases. We stabilized uniform extreme tensile strain in nanoscale La0.7Ca0.3MnO3 membranes, exceeding 8% uniaxially and 5% biaxially. Uniaxial and biaxial strain suppresses the ferromagnetic metal at distinctly different strain values, inducing an insulator that can be extinguished by a magnetic field. Electronic structure calculations indicate that the insulator consists of charge-ordered Mn4+ and Mn3+ with staggered strain-enhanced Jahn-Teller distortions within the plane. This highly tunable strained membrane approach provides a broad opportunity to design and manipulate correlated electron states.