Aharonov-Bohm oscillations in Dirac semimetal Cd3As2 nanowires.
Aharonov-Bohm oscillations in Dirac semimetal Cd3As2 nanowires.
复制标题
狄拉克半金属 Cd3As2 纳米线中的阿哈罗诺夫-玻姆振荡
DOI：
10.1038/ncomms10769
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发表时间：
2016-02-23
影响因子：
16.6
通讯作者：
Liao ZM
中科院分区：
文献类型：
--
作者：
Wang LX;Li CZ;Yu DP;Liao ZM
三维狄拉克半金属是石墨烯的三维类似物，是一种不寻常的量子材料，具有无质量狄拉克费米子，可以通过打破时间反转或反演对称性进一步转换为韦尔费米子。费米弧的拓扑表面态在表面上被预测，并通过角分辨光电子能谱实验观察到。尽管已经证明了块状狄拉克锥的奇异输运特性，但由于块状态的高导电性，通过输运测量来揭示表面态仍然是一个挑战。在这里，我们展示了具有低载流子浓度和大表面积与体积比的单个单晶 Cd3As2 纳米线中的阿哈罗诺夫-玻姆振荡，提供了三维狄拉克半金属表面态的输运证据。此外，可以通过使用栅极电压调节费米能级来调制量子传输，从而能够更深入地了解狄拉克半金属中丰富的物理性质。 狄拉克半金属是石墨烯的三维类似物，可以支持处于体态和费米弧表面态的无质量狄拉克费米子。在这里，作者观察了 Cd3As2 纳米线上输运测量中的阿哈罗诺夫-玻姆振荡，揭示了这些奇异的表面态。
Three-dimensional Dirac semimetals, three-dimensional analogues of graphene, are unusual quantum materials with massless Dirac fermions, which can be further converted to Weyl fermions by breaking time reversal or inversion symmetry. Topological surface states with Fermi arcs are predicted on the surface and have been observed by angle-resolved photoemission spectroscopy experiments. Although the exotic transport properties of the bulk Dirac cones have been demonstrated, it is still a challenge to reveal the surface states via transport measurements due to the highly conductive bulk states. Here, we show Aharonov–Bohm oscillations in individual single-crystal Cd3As2 nanowires with low carrier concentration and large surface-to-volume ratio, providing transport evidence of the surface state in three-dimensional Dirac semimetals. Moreover, the quantum transport can be modulated by tuning the Fermi level using a gate voltage, enabling a deeper understanding of the rich physics residing in Dirac semimetals. Dirac semimetals are a three-dimensional analogue of graphene that can support massless Dirac fermions in their bulk and Fermi-arc surface states. Here, the authors observe Aharonov–Bohm oscillations in transport measurements on Cd3As2 nanowires, revealing these exotic surface states.