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Superposition of photon- and phonon- assisted tunneling in coupled quantum dots

H. Qin·A. W. Holleitner·K. Eberl·R. H. Blick
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Abstract

We report on electron transport through an artificial molecule formed by two tunnel coupled quantum dots, which are laterally confined in a two-dimensional electron system of an Al$_x$Ga$_{1-x}$As/GaAs heterostructure. Coherent molecular states in the coupled dots are probed by photon-assisted tunneling (PAT). Above 10 GHz, we observe clear PAT as a result of the resonance between the microwave photons and the molecular states. Below 8 GHz, a pronounced superposition of phonon- and photon-assisted tunneling is observed. Coherent superposition of molecular states persists under excitation of acoustic phonons.

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H. Qin, A. W. Holleitner, K. Eberl, R. H. Blick. 2001-07-11. Superposition of photon- and phonon- assisted tunneling in coupled quantum dots. https://doi.org/10.1103/physrevb.64.241302

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