Double Gate Bias Dependency of Low Temperature Conductivity of SiO2-Si-SiO2 Quantum Wells

M. Prunnila; J. M. Kivioja; J. Ahopelto

doi:10.1063/1.2730024

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arXiv · cond-mat/0611705

Double Gate Bias Dependency of Low Temperature Conductivity of SiO2-Si-SiO2 Quantum Wells

M. Prunnila·J. M. Kivioja·J. Ahopelto

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Abstract

The gate bias dependency of conductivity is examined in two Si quantum wells with well thickness tw = 7 nm and tw = 14 nm. The conductivity of the thinner device behaves smoothly whereas the thicker device shows strong non-monotonic features as a function of gate voltages. We show that a strong minimum in conductivity occurs close to the threshold of second sub-band. Another minimum is seen at high electron density at symmetric well potential. This feature is addressed to sub-band wave function delocalization in the quantization direction.

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M. Prunnila, J. M. Kivioja, J. Ahopelto. 2006-11-28. Double Gate Bias Dependency of Low Temperature Conductivity of SiO2-Si-SiO2 Quantum Wells. https://doi.org/10.1063/1.2730024

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