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arXiv · 1604.04020

Resonant tunneling spectroscopy of valley eigenstates on a hybrid double quantum dot

T. Kobayashi·J. van der Heijden·M. G. House·S. J. Hile·Pablo Asshoff·M. F. Gonzalez-Zalba·M. Vinet·M. Y. Simmons·S. Rogge
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Abstract

We report electronic transport measurements through a silicon hybrid double quantum dot consisting of a donor and a quantum dot. Transport spectra show resonant tunneling peaks involving different valley states, which illustrate the valley splitting in a quantum dot on a Si/SiO2 interface. The detailed gate bias dependence of double dot transport allows a first direct observation of the valley splitting in the quantum dot, which is controllable between 160-240 ueV with an electric field dependence 1.2 +- 0.2 meV/(MV/m). A large valley splitting is an essential requirement to implement a physical electron spin qubit in a silicon quantum dot.

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T. Kobayashi, J. van der Heijden, M. G. House, S. J. Hile, Pablo Asshoff, M. F. Gonzalez-Zalba, M. Vinet, M. Y. Simmons, S. Rogge. 2016-04-14. Resonant tunneling spectroscopy of valley eigenstates on a hybrid double quantum dot. https://doi.org/10.1063/1.4945736

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