Measurements of the electrical excitation of quantum Hall devices in the real-time domain
In this study, we have investigated the time scale of the excitation of electrons leading to a transition from the quantum Hall (QH) state to the dissipative state in the two-dimensional electron system (2DES) of GaAs/AlGaAs heterostructures with Corbino geometry. The real-time-resolved measurements were performed by applying rectangular electrical pulses of 90 ns ? tp ? 180 ns pulse widths to the contacts of QH Corbino discs with various electron mobilities (0.1 ? 106 cm2 V?1 s?1 ? ?H ? 1.6 ? 106 cm2 V?1 s?1) at the integer filling factor of ? = 2. The breakdown of the quantum Hall effect (QHE) occurs after a certain time (3 ns ? ?exc ? 30 ns, ?exc tp), which is a function of applied voltage (pulse amplitude), magnetic field, electron mobility and temperature.