Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.3/55658

Title

Transport gap in a v=1/3 quantum Hall system: a probe for skyrmions

Author(s)

Dethlefsen, Annelene F.;  Haug, Rolf J.;  Vyborny, Karel;  Certik, Ondrej;  Wojs, Arkadiusz

Abstract

Transport measurements of the activation gap at fractional filling factor 1/3 are compared to results of exact diagonalization, allowing identification of a small anti-skyrmion as the lowest excitation in the low-field regime. In agreement with theory, a crossover to spinless excitations at higher electron densities is observed. Two samples of different quality are investigated. A detailed description of the theoretical calculation of activation gaps is presented and features which should be taken into account are summarized: finite thickness, Landau level mixing, and comparison between different sizes of the model system and-whenever possible-also between different geometries (torus and sphere). Within the chosen model of disorder (entailing a single fit parameter) we obtain a good agreement between calculated energies and experimental results.

Publication type

Journal article

Research centre

Swinburne University of Technology. Faculty of Engineering and Industrial Sciences. Centre for Atom Optics and Ultrafast Spectroscopy

Source

Physical Review B: Condensed Matter and Materials Physics, Vol. 74, no. 19 (2006), Article no. 195324

Publication year

2006

FOR Code(s)

0204 Condensed Matter Physics;  0206 Quantum Physics

Keyword(s)

Electron density;  Landau levels;  Quantum Hall effect;  Skyrmions

Publisher

American Physical Society

ISSN

1098-0121

Publisher URL

http://dx.doi.org/10.1103/PhysRevB.74.195324

Copyright

Copyright © 2006 The American Physical Society.

Peer reviewed