Quantum Hall states observed in thin films of Dirac semimetal Cd3As2

被引：149

作者：

Uchida, Masaki ^{[1
,2
]}

Nakazawa, Yusuke ^{[1
,2
]}

Nishihaya, Shinichi ^{[1
,2
]}

Akiba, Kazuto ^{[3
]}

Kriener, Markus ^{[4
]}

Kozuka, Yusuke ^{[1
,2
]}

Miyake, Atsushi ^{[3
]}

Taguchi, Yasujiro ^{[4
]}

Tokunaga, Masashi ^{[3
]}

Nagaosa, Naoto ^{[1
,2
,4
]}

Tokura, Yoshinori ^{[1
,2
,4
]}

Kawasaki, Masashi ^{[1
,2
,4
]}

机构：

[1] Univ Tokyo, Dept Appl Phys, Tokyo 1138656, Japan

[2] Univ Tokyo, QPEC, Tokyo 1138656, Japan

[3] Univ Tokyo, Inst Solid State Phys, Kashiwa, Chiba 2778581, Japan

[4] RIKEN Ctr Emergent Matter Sci CEMS, Wako, Saitama 3510198, Japan

来源：

NATURE COMMUNICATIONS | 2017年 / 8卷

关键词：

DISCOVERY; TRANSPORT; CRYSTAL; GROWTH;

D O I：

10.1038/s41467-017-02423-1

中图分类号：

O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];

学科分类号：

07 ; 0710 ; 09 ;

摘要：

A well known semiconductor Cd3As2 has reentered the spotlight due to its unique electronic structure and quantum transport phenomena as a topological Dirac semimetal. For elucidating and controlling its topological quantum state, high-quality Cd3As2 thin films have been highly desired. Here we report the development of an elaborate growth technique of high-crystallinity and high-mobility Cd3As2 films with controlled thicknesses and the observation of quantum Hall effect dependent on the film thickness. With decreasing the film thickness to 10 nm, the quantum Hall states exhibit variations such as a change in the spin degeneracy reflecting the Dirac dispersion with a large Fermi velocity. Details of the electronic structure including subband splitting and gap opening are identified from the quantum transport depending on the confinement thickness, suggesting the presence of a two-dimensional topological insulating phase. The demonstration of quantum Hall states in our high-quality Cd3As2 films paves a road to study quantum transport and device application in topological Dirac semimetal and its derivative phases.

引用

页数：7

共 44 条

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