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arXiv · 0908.0173

Lifetime measurements (T1) of electron spins in Si/SiGe quantum dots

Robert R. Hayes·Andrey A. Kiselev·Matthew G. Borselli·Steven S. Bui·Edward T. Croke III·Peter W. Deelman·Brett M. Maune·Ivan Milosavljevic·Jeong-Sun Moon·Richard S. Ross·Adele E. Schmitz·Mark F. Gyure·Andrew T. Hunter
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Abstract

We have observed the Zeeman-split excited state of a spin-1/2 multi-electron Si/SiGe depletion quantum dot and measured its spin relaxation time T1 in magnetic fields up to 2 T. Using a new step-and-reach technique, we have experimentally verified the g-value of 2.0 +/- 0.1 for the observed Zeeman doublet. We have also measured T1 of single- and multi-electron spins in InGaAs quantum dots. The lifetimes of the Si/SiGe system are appreciably longer than those for InGaAs dots for comparable magnetic field strengths, but both approach one second at sufficiently low fields (< 1 T for Si, and < 0.2 T for InGaAs).

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Robert R. Hayes, Andrey A. Kiselev, Matthew G. Borselli, Steven S. Bui, Edward T. Croke III, Peter W. Deelman, Brett M. Maune, Ivan Milosavljevic, Jeong-Sun Moon, Richard S. Ross, Adele E. Schmitz, Mark F. Gyure, Andrew T. Hunter. 2009-08-03. Lifetime measurements (T1) of electron spins in Si/SiGe quantum dots. https://arxiv.org/abs/0908.0173

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