Evidence of Nonlocal Breakdown of the Integer Quantum Hall Effect.

Abstract

Current induced breakdown of the integer quantum Hall effect (QHE) is studied in GaAs $/$AlGaAs single heterostructure Hall bars at $T\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1.6$--4.2 K and $B\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}2$--6 T ( $\ensuremath{\nu}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}2$, 4, and 6). The QHE breakdown is absent over a macroscopic region in the two-dimensional electron gas channel on the side of the electron-injecting corner of the Hall bars. The observed nonlocal nature suggests that bootstrap-type electron heating is relevant to the QHE breakdown.