Transport in GaAs/Al{sub x}Ga{sub 1-x}As superlattices with narrow forbidden minibands: Low-frequency negative differential conductivity and current oscillations
- Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation)
Current-voltage characteristics have been measured and low-frequency current instabilities have been studied for GaAs/Al{sub x}Ga{sub 1-x}As superlattices with narrow forbidden minibands. At relatively low electric fields, a saw-like structure for current-voltage characteristics with alternating portions of positive and negative differential conductivity and spontaneous generation of low-frequency current oscillations with a complex frequency spectrum (varying from discrete to continuous) are observed. It is shown that the observed specific features of electron transport are caused by the spatial-temporal dynamics of electric-field domains (dipoles and monopoles). The effects of the bifurcation, hysteresis, and multistability of current-voltage characteristics are also observed. At high fields, regular features are observed and identified in the current-voltage characteristics; these features are caused by resonance tunneling of electrons between the levels of the Wannier-Stark ladders belonging to quantum wells separated by several periods.
- OSTI ID:
- 21260418
- Journal Information:
- Semiconductors, Vol. 43, Issue 2; Other Information: DOI: 10.1134/S1063782609020225; Copyright (c) 2009 Pleiades Publishing, Ltd; Country of input: International Atomic Energy Agency (IAEA); ISSN 1063-7826
- Country of Publication:
- United States
- Language:
- English
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