Optical signatures of multifold fermions in the chiral topological semimetal CoSi

Abstract

We present a comprehensive combined experimental and theoretical study of optical conductivity in the chiral topological semimetal CoSi based on the development of high-quality crystals. We reveal the presence and the energy range of various exotic multifold quasiparticles in the optical responses and provide experimental evidence for the realization of fourfold spin-3/2 fermions, which were not directly observed previously. Our work is critical to interpreting future optical and transport responses of multifold fermion materials. We believe the methods used in this work will not only stimulate future research in this class of materials but will also provide a strategy for addressing optical signatures of chiral topological fermions in solids.

Document Details

Document Type
Pub Defense Publication
Publication Date
Oct 19, 2020
Source ID
10.1073/pnas.2010752117

Entities

People

  • Adolfo G Grushin
  • Andrew M Rappe
  • Bing Xu
  • Christian Bernhard
  • Claudia Felser
  • Eugene Mele
  • Johnpierre Paglione
  • Jörn W. F. Venderbos
  • Kaustuv Manna
  • Kefeng Wang
  • Liang Wu
  • Miguel-Ángel Sanchez-Martinez
  • Tian Qiu
  • Zhenyao Fang
  • Zhuoliang Ni

Organizations

  • Army Research Office
  • Canadian Institute for Advanced Research
  • Drexel University
  • Grenoble Alpes University
  • National Science Foundation
  • Swiss National Science Foundation
  • United States Department of Energy
  • University of Fribourg
  • University of Maryland
  • University of Pennsylvania

Tags

Fields of Study

  • Physics

Readers

  • Quantum spin resonance or Electron Paramagnetic Resonance spectroscopy.
  • Systems Analysis and Design