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arXiv · 2011.12594

Tunable discrete scale invariance in transition-metal pentatelluride flakes

Yanzhao Liu·Huichao Wang·Haipeng Zhu·Yanan Li·Jun Ge·Junfeng Wang·Liang Li·Ji-Yan Dai·Jiaqiang Yan·David Mandrus·Robert Joynt·Jian Wang
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Abstract

Log-periodic quantum oscillations discovered in transition-metal pentatelluride give a clear demonstration of discrete scale invariance (DSI) in solid-state materials. The peculiar phenomenon is convincingly interpreted as the presence of two-body quasi-bound states in a Coulomb potential. However, the modifications of the Coulomb interactions in many-body systems having a Dirac-like spectrum are not fully understood. Here, we report the observation of tunable log-periodic oscillations and DSI in ZrTe5 and HfTe5 flakes. By reducing the flakes thickness, the characteristic scale factor is tuned to a much smaller value due to the reduction of the vacuum polarization effect. The decreasing of the scale factor demonstrates the many-body effect on the DSI, which has rarely been discussed hitherto. Furthermore, the cut-offs of oscillations are quantitatively explained by considering the Thomas-Fermi screening effect. Our work clarifies the many-body effect on DSI and paves a way to tune the DSI in quantum materials.

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Yanzhao Liu, Huichao Wang, Haipeng Zhu, Yanan Li, Jun Ge, Junfeng Wang, Liang Li, Ji-Yan Dai, Jiaqiang Yan, David Mandrus, Robert Joynt, Jian Wang. 2020-11-25. Tunable discrete scale invariance in transition-metal pentatelluride flakes. https://doi.org/10.1038/s41535-020-00290-6

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