Quantum phase transition and destruction of Kondo effect in pressurized SmB6

Yazhou Zhou; Qi Wu; Priscila F S Rosa; Rong Yu; Jing Guo; Wei Yi; Shan Zhang; Zhe Wang; Honghong Wang; Shu Cai; Ke Yang; Aiguo Li; Zheng Jiang; Shuo Zhang; Xiangjun Wei; Yuying Huang; Peijie Sun; Yi-Feng Yang; Zachary Fisk; Qimiao Si; Zhongxian Zhao; Liling Sun

doi:10.1016/j.scib.2017.10.008

Quantum phase transition and destruction of Kondo effect in pressurized SmB₆

Sci Bull (Beijing). 2017 Nov 15;62(21):1439-1444. doi: 10.1016/j.scib.2017.10.008. Epub 2017 Oct 24.

Authors

Yazhou Zhou¹, Qi Wu¹, Priscila F S Rosa², Rong Yu³, Jing Guo¹, Wei Yi¹, Shan Zhang¹, Zhe Wang¹, Honghong Wang¹, Shu Cai¹, Ke Yang⁴, Aiguo Li⁴, Zheng Jiang⁴, Shuo Zhang⁴, Xiangjun Wei⁴, Yuying Huang⁴, Peijie Sun¹, Yi-Feng Yang⁵, Zachary Fisk⁶, Qimiao Si⁷, Zhongxian Zhao⁸, Liling Sun⁹

Affiliations

¹ Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China.
² Department of Physics and Astronomy, University of California, Irvine, CA 92697, USA; Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
³ Department of Physics, Renmin University of China, Beijing 100872, China; Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China; Collaborative Innovation Center of Advanced Microstructures, Nanjing 210093, China.
⁴ Shanghai Synchrotron Radiation Facilities, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201204, China.
⁵ Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China; Collaborative Innovation Center of Quantum Matter, Beijing 100190, China.
⁶ Department of Physics and Astronomy, University of California, Irvine, CA 92697, USA.
⁷ Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China; Department of Physics & Astronomy, Rice University, Houston, TX 77005, USA.
⁸ Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China; Collaborative Innovation Center of Quantum Matter, Beijing 100190, China; University of Chinese Academy of Sciences, Beijing 100190, China.
⁹ Institute of Physics and Beijing National Laboratory for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100190, China; Collaborative Innovation Center of Quantum Matter, Beijing 100190, China; University of Chinese Academy of Sciences, Beijing 100190, China. Electronic address: llsun@iphy.ac.cn.

PMID: 36659393
DOI: 10.1016/j.scib.2017.10.008

Abstract

SmB₆ has been a well-known Kondo insulator for decades, but recently attracts extensive new attention as a candidate topological system. Studying SmB₆ under pressure provides an opportunity to acquire the much-needed understanding about the effect of electron correlations on both the metallic surface state and bulk insulating state. Here we do so by studying the evolution of two transport gaps (low temperature gap E_l and high temperature gap E_h) associated with the Kondo effect by measuring the electrical resistivity under high pressure and low temperature (0.3 K) conditions. We associate the gaps with the bulk Kondo hybridization, and from their evolution with pressure we demonstrate an insulator-to-metal transition at ∼4 GPa. At the transition pressure, a large change in the Hall number and a divergence tendency of the electron-electron scattering coefficient provide evidence for a destruction of the Kondo entanglement in the ground state. Our results raise the new prospect for studying topological electronic states in quantum critical materials settings.

Keywords: High pressure; Kondo insulator; SmB(6); Surface state.