论文标题
与微磁体的Si中的快速自旋谷化量子门
Fast spin-valley-based quantum gates in Si with micromagnets
论文作者
论文摘要
硅量子点中的电子自旋量子置量表有望由于可伸缩性和较长的连贯性而有望处理量子信息处理。最近进步的基本要素是使用微型磁铁。它们产生合成的自旋轨道耦合（SOC），该耦合允许高保真自旋操作以及电子自旋和空腔光子之间的强烈相互作用。为了扩展量子计算，仍有多种技术挑战要克服，包括控制山谷的自由度，这通常被认为是对自旋量子的有害的。在这里，我们表明，可以通过建设性干扰和大型自旋谷混合的效果来显着增强自旋值的电气操作。为了表征自旋控制的质量，我们还通过自旋valley混合而研究了由于电荷噪声而导致的自旋去向。增强的控制强度和自旋脱位之间的竞争产生了两个甜点，在这种甜点中，自旋量子量子的质量因素可能很高。最后，我们揭示了合成的SOC导致硅的独特自旋松弛，这解释了最近的实验。
An electron spin qubit in silicon quantum dots holds promise for quantum information processing due to the scalability and long coherence. An essential ingredient to recent progress is the employment of micromagnets. They generate a synthetic spin-orbit coupling (SOC), which allows high-fidelity spin manipulation and strong interaction between an electron spin and cavity photons. To scaled-up quantum computing, multiple technical challenges remain to be overcome, including controlling the valley degree of freedom, which is usually considered detrimental to a spin qubit. Here, we show that it is possible to significantly enhance the electrical manipulation of a spin qubit through the effect of constructive interference and the large spin-valley mixing. To characterize the quality of spin control, we also studied spin dephasing due to charge noise through spin-valley mixing. The competition between the increased control strength and spin dephasing produces two sweet-spots, where the quality factor of the spin qubit can be high. Finally, we reveal that the synthetic SOC leads to distinctive spin relaxation in silicon, which explains recent experiments.
