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Nucleus-mediated spin-flip transitions in GaAs quantum dots

Sigurdur I. Erlingsson·Yuli V. Nazarov·Vladimir I. Fal'ko
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Abstract

Spin-flip rates in GaAs quantum dots can be quite slow, thus opening up the possibilities to manipulate spin states in the dots. We present here estimations of inelastic spin-flip rates mediated by hyperfine interaction with nuclei. Under general assumptions the nucleus mediated rate is proportional to the phonon relaxation rate for the corresponding non-spin-flip transitions. The rate can be accelerated in the vicinity of a singlet-triplet excited states crossing. The small proportionality coefficient depends inversely on the number of nuclei in the quantum dot. We compare our results with known mechanisms of spin-flip in $GaAs$ quantum dot.

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Sigurdur I. Erlingsson, Yuli V. Nazarov, Vladimir I. Fal'ko. 2001-04-09. Nucleus-mediated spin-flip transitions in GaAs quantum dots. https://doi.org/10.1103/physrevb.64.195306

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