Observation of 3D acoustic quantum Hall states

Xuewei Zhang; Qiang Wei; Mian Peng; Weiyin Deng; Jiuyang Lu; Xueqin Huang; Suotang Jia; Mou Yan; Zhengyou Liu; Gang Chen

doi:10.1016/j.scib.2024.04.055

Observation of 3D acoustic quantum Hall states

Sci Bull (Beijing). 2024 Apr 26:S2095-9273(24)00304-9. doi: 10.1016/j.scib.2024.04.055. Online ahead of print.

Authors

Xuewei Zhang¹, Qiang Wei¹, Mian Peng¹, Weiyin Deng², Jiuyang Lu², Xueqin Huang², Suotang Jia¹, Mou Yan³, Zhengyou Liu⁴, Gang Chen⁵

Affiliations

¹ State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China; Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China.
² School of Physics and Optoelectronics, South China University of Technology, Guangzhou 510640, China.
³ Key Laboratory of Materials Physics, Ministry of Education, School of Physics, Zhengzhou University, Zhengzhou 450001, China; Laboratory of Zhongyuan Light, School of Physics, Zhengzhou University, Zhengzhou 450001, China; Institute of Quantum Materials and Physics, Henan Academy of Sciences, Zhengzhou 450046, China. Electronic address: yanmou@zzu.edu.cn.
⁴ Key Laboratory of Artificial Micro- and Nanostructures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan 430072, China; Institute for Advanced Studies, Wuhan University, Wuhan 430072, China. Electronic address: zyliu@whu.edu.cn.
⁵ State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China; Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China; Key Laboratory of Materials Physics, Ministry of Education, School of Physics, Zhengzhou University, Zhengzhou 450001, China; Laboratory of Zhongyuan Light, School of Physics, Zhengzhou University, Zhengzhou 450001, China; Institute of Quantum Materials and Physics, Henan Academy of Sciences, Zhengzhou 450046, China. Electronic address: chengang971@163.com.

PMID: 38762435
DOI: 10.1016/j.scib.2024.04.055

Abstract

Quantum Hall effect, the quantized transport phenomenon of electrons under strong magnetic fields, remains one of the hottest research topics in condensed matter physics since its discovery in 2D electronic systems. Recently, as a great advance in the research of quantum Hall effects, the quantum Hall effect in 3D systems, despite its big challenge, has been achieved in the bulk ZrTe₅ and Cd₃As₂ materials. Interestingly, Cd₃As₂ is a Weyl semimetal, and quantum Hall effect is hosted by the Fermi arc states on opposite surfaces via the Weyl nodes of the bulk, and induced by the unique edge states on the boundaries of the opposite surfaces. However, such intriguing edge state distribution has not yet been experimentally observed. Here, we aim to reveal experimentally the unusual edge states of Fermi arcs in acoustic Weyl system with the aid of pseudo-magnetic field. Benefiting from the macroscopic nature of acoustic crystals, the pseudo-magnetic field is introduced by elaborately designed the gradient on-site energy, and the edge states of Fermi arcs on the boundaries of the opposite surfaces are unambiguously demonstrated in experiments. Our system serves as an ideal and highly tunable platform to explore the Hall physics in 3D system, and has the potential in the application of new acoustic devices.

Keywords: Acoustic crystals; Edge states; Landau levels; Pseudo-magnetic field; Quantum Hall effects.