A fractional corner anomaly reveals higher-order topology

Abstract

In addition to having an insulating interior while at the same time supporting conducting surface states, topological insulators have many other interesting properties. Higher-order topological insulating states, where regions of interest are along edges and at corners, have been difficult to identify unambiguously. Peterson et al. developed a theoretical framework to help identify and characterize these exotic states, including a new topological marker—the fractional charge density—that can be used to detect topological states of matter when the spectroscopic probe of gapless surface states is not accessible. The agreement between experimental work and theory is encouraging for applicability to other topological platforms.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jun 05, 2020
Source ID
10.1126/science.aba7604

Entities

People

  • Christopher W Peterson
  • Gaurav Bahl
  • Taylor L. Hughes
  • Tianhe Li
  • Wladimir A Benalcazar

Organizations

  • National Science Foundation
  • Office of Naval Research
  • Pennsylvania State University
  • University of Illinois Urbana–Champaign

Tags

Fields of Study

  • Physics

Readers

  • Operations Research
  • Quantum spin resonance or Electron Paramagnetic Resonance spectroscopy.

Technology Areas

  • Microelectronics
  • Microelectronics - Graphene