INVESTIGATIONS OF THE NEGATIVE DIFFERENTIAL CONDUCTIVITY AND CURRENT BISTABILITY IN DOUBLE BARRIER n+ GaAs/(AlGa)As/GaAs/(AlGa)As/n+ GaAs RESONANT TUNNELLING DEVICES USING HIGH MAGNETIC FIELDS
Résumé
Negative differential conductivity (NDC) and current bistability in a resonant tunnelling device are investigated by examining the oscillatory structure in the magnetotunnelling current for J ||B. The data support the conclusion that bistability is associated with build-up and ejection of negative space charge from the well. The charge density of 2D electrons in the contact accumulation layer is measured directly. NDC due to tunnelling into the second sub-band of the well is observed at high bias (~ 1 V). The associated magneto-oscillations indicate the presence of sequential tunnelling in this region of the I(V) curves.
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Articles anciens
Origine : Accord explicite pour ce dépôt
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