Coulomb blockade and transport spectroscopy in short Si:MOSFET

Autor: L. Ghenim, M. Specht, Simon Deleonibus, Marc Sanquer, G. Guegan
Rok vydání: 1999
Předmět:
Zdroj: Annalen der Physik. 8:743-752
ISSN: 1521-3889
0003-3804
Popis: We report Coulomb oscillations in short (50 nm and 100 nm) and wide Silicon MOSFETs at very low temperature, when the source-drain conductance is below the quantum e2/h. the geometry is dual of a wire, where such oscillations have been previously reported. Our observations show that the dominating best conducting channel is a localized state which can accomodate several electrons. This emphasizes that Coulomb blockade appears also at low temperature in a standart short and wide transistor-like geometry, without intentional confinement, as far as the conductance is below the quantum. Analysis of the non-linear transport permits to evaluate both the mean one electron spacing (few kelvins) and the Coulomb energy (few tens of kelvins). At finite transport voltage the contributions of excited states are observed. Comparing the 50 nm and 100 nm series, we find that the size of the impurity quantum dot roughly scales with the source-drain distance.
Databáze: OpenAIRE
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