Current Breakdown of the Fractional Quantum Hall Effect through Contactless Detection of Induced Currents

J. P. Watts; A. Usher; A. J. Matthews; M. Zhu; M. Elliott; W. G. Herrenden-Harker; P. R. Morris; M. Y. Simmons; D. A. Ritchie

doi:10.1103/PhysRevLett.81.4220

Current Breakdown of the Fractional Quantum Hall Effect through Contactless Detection of Induced Currents

J. P. Watts, A. Usher, A. J. Matthews, M. Zhu, M. Elliott, W. G. Herrenden-Harker, P. R. Morris, M. Y. Simmons, and D. A. Ritchie

Phys. Rev. Lett. 81, 4220 – Published 9 November 1998

Abstract

We have observed induced currents associated with the fractional quantum Hall effect (FQHE) in a contactless two-dimensional electron gas subjected to a sweeping magnetic field. Their current-voltage characteristics exhibit pronounced nonlinearities caused by the breakdown of the FQHE at high currents. Our results support the inter-Landau-level-scattering model of breakdown and provide a new local probe of the FQHE energy gaps at $ν = 1 / 3$ and $2 / 3$ . They are also consistent with the composite-fermion picture but yield an effective mass significantly smaller than previously reported values.

Received 9 March 1998

DOI:https://doi.org/10.1103/PhysRevLett.81.4220

Authors & Affiliations

J. P. Watts¹, A. Usher¹, A. J. Matthews¹, M. Zhu¹, M. Elliott², W. G. Herrenden-Harker², P. R. Morris², M. Y. Simmons³, and D. A. Ritchie³

¹School of Physics, University of Exeter, Stocker Road, Exeter, EX4 4QL, United Kingdom
²Department of Physics and Astronomy, University of Wales College of Cardiff, P.O. Box 913, Cardiff, CF1 9HQ, United Kingdom
³Cavendish Laboratory, University of Cambridge, Madingley Road, Cambridge, CB3 0HE, United Kingdom