Wolfowicz Gary, Urdampilleta Matias, Thewalt Mike L W, Riemann Helge, Abrosimov Nikolai V, Becker Peter, Pohl Hans-Joachim, Morton John J L
London Centre for Nanotechnology, University College London, London WC1H 0AH, United Kingdom and Department of Materials, Oxford University, Oxford OX1 3PH, United Kingdom.
London Centre for Nanotechnology, University College London, London WC1H 0AH, United Kingdom.
Phys Rev Lett. 2014 Oct 10;113(15):157601. doi: 10.1103/PhysRevLett.113.157601. Epub 2014 Oct 6.
Electric fields can be used to tune donor spins in silicon using the Stark shift, whereby the donor electron wave function is displaced by an electric field, modifying the hyperfine coupling between the electron spin and the donor nuclear spin. We present a technique based on dynamic decoupling of the electron spin to accurately determine the Stark shift, and illustrate this using antimony donors in isotopically purified silicon-28. We then demonstrate two different methods to use a dc electric field combined with an applied resonant radio-frequency (rf) field to conditionally control donor nuclear spins. The first method combines an electric-field induced conditional phase gate with standard rf pulses, and the second one simply detunes the spins off resonance. Finally, we consider different strategies to reduce the effect of electric field inhomogeneities and obtain above 90% process fidelities.
电场可利用斯塔克位移来调控硅中的施主自旋，即电场使施主电子波函数发生位移，从而改变电子自旋与施主核自旋之间的超精细耦合。我们提出一种基于电子自旋动态解耦的技术来精确测定斯塔克位移，并在同位素纯化的硅 - 28中使用锑施主对此进行说明。然后，我们展示了两种不同的方法，即结合直流电场与外加共振射频（rf）场来有条件地控制施主核自旋。第一种方法将电场诱导的条件相位门与标准射频脉冲相结合，第二种方法则简单地使自旋失谐。最后，我们考虑了不同的策略来降低电场不均匀性的影响，并获得高于90%的过程保真度。
