Rectification in Quantum Hall Effect Devices Above Breakdown
Kevin C. Lee
Three-terminal contract resistances of 180 contacts on 15 quantum Hall effect (QHE) devices were measured as a function of current at the center of the I = 4 plateau at temperatures between 1.1 K and 1.4 K. For current densities less than about 1.5 A/m, the behavior of the contact is governed by well-know Landau level conduction: the contact resistance vanishes below a critical current and increases sharply above it as the QHE breaks down. For currents densities above 1.5 A/m, most contacts reported to date have resistances which are generally independent of current (i.e., ohmic). Several contacts tested in this work, however, exhibited novel rectifying characteristics: at current densities less than 1.5 A/m, the contact resistances exhibited the current dependence typical of an ideal contact, but at current densities above breakdown, the contact resistance in the forward direction had a current-independent value typically about 200 ohms. The contact resistance in the reverse direction increase rapidly to very high values. Furthermore, dI/dV was linearly proportional to the current above breakdown. It is proposed that this rectifying behavior is caused by a potential barrier that only affects hot electron transport in the high-current regime.
Bulletin of the American Physical Society
breakdown, hetelectron transport, Landau levels, quantum Hall effect, rectification
Rectification in Quantum Hall Effect Devices Above Breakdown, Bulletin of the American Physical Society
(Accessed June 9, 2023)