Department of Physics, Brown University, Providence, Rhode Island 02912, USA.
National High Magnetic Field Laboratory, Tallahassee, Florida 32310, USA.
Nat Commun. 2017 Feb 9;8:14407. doi: 10.1038/ncomms14407.
Study of the combined effects of strong electronic correlations with spin-orbit coupling (SOC) represents a central issue in quantum materials research. Predicting emergent properties represents a huge theoretical problem since the presence of SOC implies that the spin is not a good quantum number. Existing theories propose the emergence of a multitude of exotic quantum phases, distinguishable by either local point symmetry breaking or local spin expectation values, even in materials with simple cubic crystal structure such as BaNaOsO. Experimental tests of these theories by local probes are highly sought for. Our local measurements designed to concurrently probe spin and orbital/lattice degrees of freedom of BaNaOsO provide such tests. Here we show that a canted ferromagnetic phase which is preceded by local point symmetry breaking is stabilized at low temperatures, as predicted by quantum theories involving multipolar spin interactions.
强电子相关与自旋轨道耦合（SOC）的联合效应研究是量子材料研究的核心问题。由于 SOC 的存在意味着自旋不是一个好的量子数，因此预测新出现的性质是一个巨大的理论问题。现有理论提出了多种奇异量子相的出现，这些量子相可以通过局部点对称性破缺或局部自旋期望值来区分，即使在具有简单立方晶体结构的材料中也是如此，例如 BaNaOsO。因此，人们高度期望通过局部探针对这些理论进行实验验证。我们设计的针对 BaNaOsO 的自旋和轨道/晶格自由度的局部测量提供了这样的测试。在这里，我们表明，正如涉及多极自旋相互作用的量子理论所预测的那样，在低温下，通过局部点对称性破缺稳定了倾斜铁磁相。
