论文标题
GAAS/藻类量子点的中央自旋系统中的核自旋扩散
Nuclear spin diffusion in the central spin system of a GaAs/AlGaAs quantum dot
论文作者
论文摘要
自旋扩散概念提供了对不均匀极化多体系统（例如核自旋晶格）中纯粹量子力学进化的经典描述。局部电子的中心自旋以仍然知之甚少的方式改变了核自旋扩散。与以前的预测相反，我们通过实验表明，在GAAS/藻类量子中，电子旋转会加速核自旋扩散，而不会形成任何骑士场梯度屏障。即使在高磁场上也存在这样的加速度，我们可以解释这是电子自旋波动的结果。扩散限制的核自旋寿命范围在1到10 s之间，为最近的建议提供了足够的空间，以寻求使用量子点核自旋存储和处理量子信息。
The spin diffusion concept provides a classical description of a purely quantum-mechanical evolution in inhomogeneously polarized many-body systems such as nuclear spin lattices. The central spin of a localized electron alters nuclear spin diffusion in a way that is still poorly understood. In contrast to previous predictions, we show experimentally that in GaAs/AlGaAs quantum dots the electron spin accelerates nuclear spin diffusion, without forming any Knight field gradient barrier. Such acceleration is present even at high magnetic fields, which we explain as a result of electron spin-flip fluctuations. Diffusion-limited nuclear spin lifetimes range between 1 and 10 s, providing plenty of room for recent proposals seeking to store and process quantum information using quantum dot nuclear spins.
