Observation of Unconventional Quantum Spin Textures in Topological Insulators
Observation of Unconventional Quantum Spin Textures in Topological Insulators
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DOI：
10.1126/science.1167733
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发表时间：
2009-02-13
期刊：
影响因子：
56.9
通讯作者：
Hasan, M. Z.
中科院分区：
文献类型：
--
作者：
Hsieh, D.;Xia, Y.;Hasan, M. Z.
拓扑有序材料的特征在于罕见的电子量子组织，其回避了传统的基于自发破缺对称性的凝聚态物质分类。奇异的自旋输运现象，如无耗散的量子自旋霍尔效应，被推测起源于一种拓扑秩序，其识别需要自旋敏感的测量，这在任何系统中都不存在。利用Mott旋光法，我们探测了自旋自由度，并证明了拓扑量子数完全由自旋纹理成像测量确定。将此方法应用于Sb和Bi 1-xSbx，我们确定了其拓扑顺序和不寻常的手性性质的起源。这些结果一起构成了表面电子集体携带拓扑量子Berry相位和确定的自旋手性的第一次观察，这是用于实现具有内在自旋Hall拓扑现象的拓扑量子计算比特的关键电子性质组分。
A topologically ordered material is characterized by a rare quantum organization of electrons that evades the conventional spontaneously broken symmetry- based classification of condensed matter. Exotic spin- transport phenomena, such as the dissipationless quantum spin Hall effect, have been speculated to originate from a topological order whose identification requires a spin- sensitive measurement, which does not exist to this date in any system. Using Mott polarimetry, we probed the spin degrees of freedom and demonstrated that topological quantum numbers are completely determined from spin texture- imaging measurements. Applying this method to Sb and Bi1-xSbx, we identified the origin of its topological order and unusual chiral properties. These results taken together constitute the first observation of surface electrons collectively carrying a topological quantum Berry's phase and definite spin chirality, which are the key electronic properties component for realizing topological quantum computing bits with intrinsic spin Hall- like topological phenomena.