Abstract
Semi-insulating GaAs samples show low-frequency current oscillations (LFO) under high dc voltage. These spontaneous oscillations are caused by traveling high-electric-field domains and can be explained based on the well-accepted model of electron trapping in deep levels by multiphonon emission processes. This paper aims to explain today the most important open question about LFO, namely, the cause of the very slow propagation of the domain resulting in the low frequencies. Our claim is that hopping conduction acts as a low mobility barrier for the free carriers leading to the formation of the electric-field domains. The barrier blocks, through a Coulomb shield, the flow of the high mobility free carriers leading to a charge accumulation, which produces the current pulse in the external circuit when the domain reaches the anode where it is destroyed. LFO occurs, therefore, only in the regime of band and hopping mixed conduction mechanisms.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
