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arXiv · 2103.06409

Measurement of tunnel coupling in a Si double quantum dot based on charge sensing

Xinyu Zhao·Xuedong Hu
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Abstract

In Si quantum dots, valley degree of freedom, in particular the generally small valley splitting and the dot-dependent valley-orbit phase, adds complexities to the low-energy electron dynamics and the associated spin qubit manipulation. Here we propose a four-level model to extract tunnel coupling information for a Si double quantum dot (DQD). This scheme is based on a charge sensing measurement on the ground state as proposed in the widely used protocol for a GaAs double dot [DiCarlo et. al., PRL 92. 226801]. Our theory can help determine both intra- and inter-valley tunnel coupling with high accuracy, and is robust against system parameters such as valley splittings in the individual quantum dots.

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Xinyu Zhao, Xuedong Hu. 2021-03-11. Measurement of tunnel coupling in a Si double quantum dot based on charge sensing. https://doi.org/10.1103/physrevapplied.17.064043

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