Multiple channel transport properties of topological surface states in SmB6 nanoribbons
Multiple channel transport properties of topological surface states in SmB6 nanoribbons
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DOI：
10.1063/5.0174485
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发表时间：
2023-12
影响因子：
4
通讯作者：
Yujiao Ma;Yugui Cui;Yi Chu;Yan Xu;Yingjie Xing;Shaoyun Huang
中科院分区：
文献类型：
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作者：
Yujiao Ma;Yugui Cui;Yi Chu;Yan Xu;Yingjie Xing;Shaoyun Huang
SmB 6，拓扑近藤绝缘体，具有拓扑保护的表面状态，其中载流子迁移率应该是高的，但显着变化的数量级取决于表征方法。在此，我们进行了磁阻测量霍尔条器件上构建的高度均匀的SmB 6纳米晶（001）表面生长的化学气相沉积。在低温下观察到非线性霍尔电阻，并用双载流子模型进行了解释。这两种载流子的产生归因于SmB 6（001）表面布里渊区的两种费米口袋。在2.2K温度下，位于Γ点的费米口袋提供了高达1.4×103 cm ~ 2/Vs的高空穴迁移率，但空穴密度较低。另一方面，费米口袋上的X点提供低电子迁移率下降到1.8 cm 2/V s，但高电子密度。这两类口袋的识别为理解SmB 6（001）表面的拓扑表面态输运奠定了基础。
SmB6, a topological Kondo insulator, possesses topologically protected surface states, in which carrier mobility is supposed to be high but is significantly varied in orders of magnitude dependent upon characterization methods. Herein, we performed magnetoresistance measurements on a Hall-bar device constructed on a highly uniform SmB6 nanoribbon with (001) surface grown by chemical vapor deposition. Unusual non-linear Hall resistance was observed at low temperature and explained with a two-carrier model. The two types of carriers were attributed to two types of Fermi pockets on the Brillouin zone of the SmB6 (001) surface. The Fermi pocket on Γ point provided high hole mobility up to 1.4×103 cm2/V s but low hole density at a temperature of 2.2 K. On the other hand, the Fermi pockets on X points supplied low electron mobility down to 1.8 cm2/V s but high electron density. The identification of the two types of pockets laid the foundation for the understanding of the transport via the topological surface states of the SmB6 (001) surface.