New Journal of Physics

Back-action-driven electron spin excitation in a single quantum dot

Gang Cao, Ming Xiao, Hai-Ou Li, Cheng Jun Zhou, Runan Shang, Tao Tu, H. W. Jiang, Guo‐Ping Guo

Published Feb 13, 2013• 4 citations

Abstract

We perform real-time charge counting with a quantum point contact (QPC) for the last six electrons in a single quantum dot. At zero magnetic field, the charge-counting statistics show distinctive non-thermal-equilibrium effects for the even and odd electron numbers. A detailed study relates this difference to the excitation from the spin singlet state to triplet states driven by QPC back-action. At a finite magnetic field, spin excitations to different triplet states and Zeeman states are also observed. A master-equation model is developed to quantitatively characterize the back-action-driven spin excitation rate.

DOI: 10.1088/1367-2630/15/2/023021

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