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arXiv · 1808.05303

Difference in charge and spin dynamics in a quantum dot-lead coupled system

Tomohiro Otsuka·Takashi Nakajima·Matthieu R. Delbecq·Peter Stano·Shinichi Amaha·Jun Yoneda·Kenta Takeda·Giles Allison·Sen Li·Akito Noiri·Takumi Ito·Daniel Loss·Arne Ludwig·Andreas D. Wieck·Seigo Tarucha
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Abstract

We analyze time evolution of charge and spin states in a quantum dot coupled to an electric reservoir. Utilizing high-speed single-electron detection, we focus on dynamics induced by the first-order tunneling. We find that there is a difference between the spin and the charge relaxation: the former appears slower than the latter. The difference depends on the Fermi occupation factor and the spin relaxation becomes slower when the energy level of the quantum dot is lowered. We explain this behavior by a theory which includes the first-order tunneling processes. We conduct detailed comparison of the experiment and the theory with changing the energy of the quantum dot levels, and the theory can reproduce the experimental results.

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Tomohiro Otsuka, Takashi Nakajima, Matthieu R. Delbecq, Peter Stano, Shinichi Amaha, Jun Yoneda, Kenta Takeda, Giles Allison, Sen Li, Akito Noiri, Takumi Ito, Daniel Loss, Arne Ludwig, Andreas D. Wieck, Seigo Tarucha. 2018-08-15. Difference in charge and spin dynamics in a quantum dot-lead coupled system. https://doi.org/10.1103/physrevb.99.085402

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