title: Giant Fano factor and bistability in a Corbino disk in the quantum Hall effect breakdown regime.
abstract: We performed noise measurements for a Corbino disk in the quantum Hall effect breakdown regime. We investigated two Corbino-disk-type devices with different sizes and observed that the Fano factor increases when the length between the contacts doubles. This observation is consistent with the avalanche picture suggested by the bootstrap electron heating model. The temperature dependence of the Fano factor indicates that the avalanche effect becomes more prominent as temperature decreases. Moreover, in the highly nonlinear regime, negative differential resistance and temporal oscillation due to bistability are found. A possible interpretation of this result is that Zener tunneling of electrons between Landau levels occurs.
authors.affiliation: Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan.
authors.forename: Tokuro
authors.initials: T
authors.lastname: Hata
authors.forename: Tomonori
authors.initials: T
authors.lastname: Arakawa
authors.forename: Kensaku
authors.initials: K
authors.lastname: Chida
authors.forename: Sadashige
authors.initials: S
authors.lastname: Matsuo
authors.forename: Kensuke
authors.initials: K
authors.lastname: Kobayashi