Spectroscopy of double quantum dot two-spin states by tuning the inter-dot barrier

G. Giavaras; Y. Tokura

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arXiv · 1902.01979

Spectroscopy of double quantum dot two-spin states by tuning the inter-dot barrier

G. Giavaras·Y. Tokura

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Abstract

Transport spectroscopy of two-spin states in a double quantum dot can be performed by an AC electric field which tunes the energy detuning. However, a problem arises when the transition rate between the states is small and, consequently, the AC-induced current is suppressed. Here, we show that if the AC field tunes the inter-dot tunnel barrier then for large detuning the transition rate increases drastically resulting in high current. Multi-photon resonances are enhanced by orders of magnitude. Our study demonstrates an efficient way for fast two-spin transitions.

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G. Giavaras, Y. Tokura. 2019-02-05. Spectroscopy of double quantum dot two-spin states by tuning the inter-dot barrier. https://arxiv.org/abs/1902.01979

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