Evidence for Dirac nodes from quantum oscillations in SrFe2As2

Scientific paper - Original scientific paper

• Author: Mike Sutherland
• Author: D. J. Hills
• Author: B. S. Tan
• Author: M. M. Altarawneh
• Author: N. Harrison
• Author: J. Gillett
• Author: E. C. T. O'Farrell
• Author: T. M. Benseman
• Author: Ivan Kokanović
• Author: P. Syers
• Author: J. R. Cooper
• Author: Suchitra E. Sebastian
• Author's institution: University of Zagreb; Faculty of Science; (Department of Physics)
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Physics

Abstract (english)

We present a detailed study of quantum oscillations in the antiferromagnetically ordered pnictide compound SrFe2As2 as the angle between the applied magnetic field and crystalline axes is varied. Our measurements were performed on high-quality single crystals in a superconducting magnet, and in pulsed magnetic fields up to 60 T, allowing us to observe orbits from several small Fermi-surface pockets. We extract the cyclotron effective mass m☆ and frequency F for these orbits and track their values as the field is rotated away from the c axis. While a constant ratio of m☆/F is expected for a parabolic band, we observe deviations from this behavior. We conclude that this observation points to orbits derived from a band with Dirac dispersion near the Fermi level.

• Keywords (english): pnictide compound SrFe2As2; quantum oscillations; Dirac Nodes
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review - international
• Publication version: Published version
• Journal title: Physical review B: Condensed matter and materials physics
• Numbering: vol. 84, no. 18, 180506(R)
• p-ISSN: 1098-0121
• e-ISSN: 1550-235X
• DOI: https://doi.org/10.1103/PhysRevB.84.180506
• URN:NBN: urn:nbn:hr:217:725614
• Publication: 2011
• Project: Number: 119-1191458-1008; Title (croatian): Električna i magnetska svojstva odabranih anorganskih i organskih materijala; Leader: Ivan Kokanović; Jurisdiction: Croatia; Funding stream: ZP
• Document URL: http://link.aps.org/doi/10.1103/PhysRevB.84.180506
• Type of resource: Text
• Access conditions: Open access
• Public note: Copyright (2011) by the American Physical Society. Received 8 July 2011; revised manuscript received 2 August 2011; published 14 November 2011.
• Created on: 2019-11-15 17:01:16