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arXiv · 1005.5077

Andreev reflection enhanced single hole tunneling in Ge/Si core/shell nanowire quantum dot

Xiao-Jie Hao·Guo-Ping Guo·Hai-Ou Li·Cheng Zhou·Gang Cao·Guang-Can Guo·Wayne Y. Fung·Zhongqing Ji·Wei Lu·Tao Tu
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Abstract

We experimentally study the electrical transport properties of Ge/Si core/shell nanowire device with two superconducting leads in the Coulomb blockade regime. Anomalous zero field magnetoconductance peaks are observed for the first time at the gate voltages where Coulomb blockade oscillation peaks present. Many evidences indicate this feature is due to Andreev reflection enhanced phase coherent single hole tunneling through the quantum dot, which can be suppressed by an external magnetic field without destroying the superconducting states in the electrodes.

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Xiao-Jie Hao, Guo-Ping Guo, Hai-Ou Li, Cheng Zhou, Gang Cao, Guang-Can Guo, Wayne Y. Fung, Zhongqing Ji, Wei Lu, Tao Tu. 2010-05-27. Andreev reflection enhanced single hole tunneling in Ge/Si core/shell nanowire quantum dot. https://arxiv.org/abs/1005.5077

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