Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Spin polarization and g-factor enhancement in graphene nanoribbons in a magnetic field
Simon Fraser University, Canada .
Linköping University, Department of Science and Technology, Physics and Electronics. Linköping University, The Institute of Technology.
2012 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 86, no 15, 155407- p.Article in journal (Refereed) Published
Abstract [en]

We provide a systematic quantitative description of spin polarization in armchair and zigzag graphene nanoribbons (GNRs) in a perpendicular magnetic field. We first address spinless electrons within the Hartree approximation, studying the evolution of the magnetoband structure and formation of the compressible strips. We discuss the potential profile and the density distribution near the edges and the difference and similarities between armchair and zigzag edges. Accounting for the Zeeman interaction and describing the spin effects via the Hubbard term, we study the spin-resolved subband structure and relate the spin polarization of the system at hand to the formation of the compressible strips for the case of spinless electrons. At high magnetic field the calculated effective g factor varies around a value of andlt; g*andgt; approximate to 2.25 for armchair GNRs and andlt; g*andgt; approximate to 3 for zigzag GNRs. An important finding is that in zigzag GNRs the zero-energy mode remains pinned to the Fermi energy and becomes fully spin polarized for all magnetic fields, which, in turn, leads to a strong spin polarization of the electron density near the zigzag edge. Because of this the effective g factor in zigzag GNRs is strongly enhanced at low fields reaching values up to g* approximate to 30. This is in contrast to armchair GNRs, where the effective g factor at low field is close to its bare value, g = 2.

Place, publisher, year, edition, pages
American Physical Society , 2012. Vol. 86, no 15, 155407- p.
National Category
Engineering and Technology
Identifiers
URN: urn:nbn:se:liu:diva-85196DOI: 10.1103/PhysRevB.86.155407ISI: 000309578700004OAI: oai:DiVA.org:liu-85196DiVA: diva2:566679
Note

Funding Agencies|Swedish Institute||

Available from: 2012-11-09 Created: 2012-11-09 Last updated: 2017-12-07

Open Access in DiVA

fulltext(1768 kB)