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Quantum oscillations from surface Fermi arcs in Weyl and Dirac semimetals
Andrew C Potter1, Itamar Kimchi1, Ashvin Vishwanath1
1Department of Physics, University of California, Berkeley, California 94720, USA.
Nature Communications
|October 21, 2014
Summary
Open Fermi arcs in Weyl semimetals form unusual magnetic orbits, enabling observation of topological properties through quantum oscillations. This study reveals new signatures for detecting these exotic surface states in materials like Cd3As2 and Na3Bi.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Mechanics
Background:
- Electrons in metals form closed orbits in magnetic fields, enabling Fermi surface studies via quantum oscillations.
- Weyl semimetals feature open Fermi arcs, posing challenges for observation with standard quantum oscillatory techniques.
Purpose of the Study:
- To investigate whether open Fermi arcs in Weyl semimetals can participate in observable quantum oscillations.
- To identify unique magnetic orbits and signatures indicative of topological properties in Weyl semimetals.
Main Methods:
- Theoretical analysis of electron behavior in magnetic fields within Weyl semimetals.
- Identification of anomalous closed magnetic orbits formed by open Fermi arcs traversing the bulk.
- Application of predictions to specific materials like Cd3As2 and Na3Bi.
Main Results:
- Open Fermi arcs in Weyl semimetals form unusual closed magnetic orbits by connecting opposite surfaces through the bulk.
- These orbits exhibit anomalous features distinct from conventional surface states.
- Quantum oscillations reveal observable signatures of the bulk topological character.
Conclusions:
- Quantum oscillations can detect and characterize the topological Fermi arc states in Weyl semimetals.
- The findings provide a framework for experimental observation of these exotic states.
- Proposed experimental signatures for Dirac (doubled Weyl) semimetals Cd3As2 and Na3Bi.
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