Ultraquantum magnetoresistance in the Kramers-Weyl semimetal candidate βAg2Se

Cheng-Long Zhang, Frank Schindler, Haiwen Liu, Tay-Rong Chang, Su-Yang Xu, Guoqing Chang, Wei Hua, Hua Jiang, Zhujun Yuan, Junliang Sun, Horng-Tay Jeng, Hai-Zhou Lu, Hsin Lin, M. Zahid Hasan, X. C. Xie, Titus Neupert, and Shuang Jia
Phys. Rev. B 96, 165148 – Published 26 October 2017

Abstract

The topological semimetal βAg2Se features a Kramers-Weyl node at the origin in momentum space and a quadruplet of spinless Weyl nodes, which are annihilated by spin-orbit coupling. We show that single-crystalline βAg2Se manifests giant Shubnikov–de Haas oscillations in the longitudinal magnetoresistance, which stem from a small electron pocket that can be driven beyond the quantum limit by a field less than 9 T. This small electron pocket is a remainder of the spin-orbit annihilated Weyl nodes and thus encloses a Berry-phase structure. Moreover, we observed a negative longitudinal magnetoresistance when the magnetic field is beyond the quantum limit. Our experimental findings are complemented by thorough theoretical band-structure analyses of this Kramers-Weyl semimetal candidate, including first-principles calculations and an effective k·p model.

  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
1 More
  • Received 7 August 2017

DOI:https://doi.org/10.1103/PhysRevB.96.165148

©2017 American Physical Society

Physics Subject Headings (PhySH)

Condensed Matter, Materials & Applied Physics

Authors & Affiliations

Cheng-Long Zhang1, Frank Schindler2, Haiwen Liu3, Tay-Rong Chang4, Su-Yang Xu5, Guoqing Chang6,7, Wei Hua8, Hua Jiang9, Zhujun Yuan1, Junliang Sun8, Horng-Tay Jeng4,10, Hai-Zhou Lu11, Hsin Lin6,7, M. Zahid Hasan5, X. C. Xie1,12, Titus Neupert2, and Shuang Jia1,12,*

  • 1International Center for Quantum Materials and School of Physics, Peking University, Beijing 100871, China
  • 2Department of Physics, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland
  • 3Center for Advanced Quantum Studies, Department of Physics, Beijing Normal University, Beijing 100875, China
  • 4Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan, Republic of China
  • 5Joseph Henry Laboratory, Department of Physics, Princeton University, Princeton, New Jersey 08544, USA
  • 6Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore, 6 Science Drive 2, Singapore 117546
  • 7Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117542
  • 8Department of Chemistry, Peking University, Beijing 100871, China
  • 9College of Physics, Optoelectronics and Energy, Soochow University, Suzhou 215006, China
  • 10Institute of Physics, Academia Sinica, Taipei 11529, Taiwan, Republic of China
  • 11Department of Physics, South University of Science and Technology of China, Shenzhen 518055, China
  • 12Collaborative Innovation Center of Quantum Matter, Beijing 100871, China

  • *gwljiashuang@pku.edu.cn

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 96, Iss. 16 — 15 October 2017

Reuse & Permissions
Access Options
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review B

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×