Electronic Processes at the Breakdown of the Quantum Hall Effect.pdf

typeset using JPSJ.sty ver.1.0b Electronic Processes at the Breakdown of the Quantum Hall Effect ∗ Hiroshi Akera∗∗ 0 0 Department of Applied Physics, Hokkaido University, Sapporo 060-8628 0 2 (Received June 29, 2000) n u Microscopic processes giving the energy gain and loss of a two-dimensional electron system J in long-range potential fluctuations are studied theoretically at the breakdown of the quantum Hall effect in the case of even-integer filling factors. The Coulomb scattering within a broadened 0 Landau level is proposed to give the gain, while the phonon scattering to give the loss. The 3 energy balance equation shows that the electron temperature Te and the diagonal conductivity σxx exhibit a bistability above the lower critical electric field Ec1. Calculated values of Ec1 as ] l well as Te and σxx at Ec1 are in agreement with the observed values in their orders of magnitude. l a h KEYWORDS: integer quantum Hall effect, nonlinear transport, theory - s e m 1,2) ˚ . In the quantum Hall effect (QHE), the diagonal the layer several hundred A above 2DES, and its im- t a conductivity σxx is vanishingly small in the low-current portance in the breakdown of QHE has been discussed m regime. When the current is increased up to a criti- in the literature.9,12,14,18) Fl