Nowack K C, Koppens F H L, Nazarov Yu V, Vandersypen L M K
Kavli Institute of Nanoscience, Delft University of Technology, Post Office Box 5046, 2600 GA Delft, the Netherlands.
Science. 2007 Nov 30;318(5855):1430-3. doi: 10.1126/science.1148092. Epub 2007 Nov 1.
Manipulation of single spins is essential for spin-based quantum information processing. Electrical control instead of magnetic control is particularly appealing for this purpose, because electric fields are easy to generate locally on-chip. We experimentally realized coherent control of a single-electron spin in a quantum dot using an oscillating electric field generated by a local gate. The electric field induced coherent transitions (Rabi oscillations) between spin-up and spin-down with 90 degrees rotations as fast as approximately 55 nanoseconds. Our analysis indicated that the electrically induced spin transitions were mediated by the spin-orbit interaction. Taken together with the recently demonstrated coherent exchange of two neighboring spins, our results establish the feasibility of fully electrical manipulation of spin qubits.
单自旋的操控对于基于自旋的量子信息处理至关重要。为此，采用电控制而非磁控制特别具有吸引力，因为电场易于在芯片上局部产生。我们通过使用局部栅极产生的振荡电场，在实验上实现了对量子点中单个电子自旋的相干控制。该电场诱导自旋向上和自旋向下之间的相干跃迁（拉比振荡），90度旋转的速度快至约55纳秒。我们的分析表明，电诱导的自旋跃迁是由自旋 - 轨道相互作用介导的。结合最近证明的两个相邻自旋的相干交换，我们的结果确立了对自旋量子比特进行全电操控的可行性。
