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arXiv · 1202.3237

Few electron double quantum dot in an isotopically purified $^{28}$Si quantum well

Andreas Wild·Johannes Kierig·Jürgen Sailer·Joel Ager III·Eugene Haller·Gerhard Abstreiter·Stefan Ludwig·Dominique Bougeard
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Abstract

We present a few electron double quantum dot (QD) device defined in an isotopically purified $^{28}$Si quantum well (QW). An electron mobility of $5.5 \cdot 10^4 cm^2(Vs)^{-1}$ is observed in the QW which is the highest mobility ever reported for a 2D electron system in $^{28}$Si. The residual concentration of $^{29}$Si nuclei in the $^{28}$Si QW is lower than $10^{3} ppm$, at the verge where the hyperfine interaction is theoretically no longer expected to dominantly limit the $T_{2}$ spin dephasing time. We also demonstrate a complete suppression of hysteretic gate behavior and charge noise using a negatively biased global top gate.

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Andreas Wild, Johannes Kierig, Jürgen Sailer, Joel Ager III, Eugene Haller, Gerhard Abstreiter, Stefan Ludwig, Dominique Bougeard. 2012-02-15. Few electron double quantum dot in an isotopically purified $^{28}$Si quantum well. https://doi.org/10.1063/1.3701588

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