High-speed high-current field switching of NbO2

Abstract

The field-switching properties of NbO2/NbO or NbO2/(reduced NbO2) devices have been investigated. Under an applied electric field they switch from a high (≳10 kΩ) to a low (∼10 Ω) resistance in times shorter than 0.7 ns. For pulse durations of several ns, the current carrying capability is higher than 80 A. The switching mechanism appears to proceed in two stages: the field-assisted Poole-Frenkel mechanism for low applied field and thermal runaway. However, the unique switching properties of NbO2 could also be understood by a small poloron-conduction mechanism.