论文标题
量子点电子自旋的驱动动力学与高自旋核的浴
Driven dynamics of a quantum dot electron spin coupled to bath of higher-spin nuclei
论文作者
论文摘要
限制在量子点及其周围核自旋环境的电子之间的光学驾驶和超精细相互作用的相互作用会产生一系列有趣的物理，例如模式锁定。在这项工作中，我们超越了核自旋的无处不在的自旋1/2近似，并为在自组装的量子点中与核自旋的核自旋浴中的光学驱动电子旋转提供了全面的理论框架。使用动态平均场方法，我们计算有或没有四极耦合的核自旋极化分布。我们发现，虽然超细相互作用驱动动态核极化和模式锁定，但四极耦合抵消了这些效果。这些机制之间的张力印在稳态电子自旋演变上，提供了一种测量量子点中四极相互作用的重要性的方法。我们的结果表明，诸如四极相互作用之类的较高自旋效应可能会对动态核极化的产生产生重大影响，以及它如何影响电子自旋进化。
The interplay of optical driving and hyperfine interaction between an electron confined in a quantum dot and its surrounding nuclear spin environment produces a range of interesting physics such as mode-locking. In this work, we go beyond the ubiquitous spin 1/2 approximation for nuclear spins and present a comprehensive theoretical framework for an optically driven electron spin in a self-assembled quantum dot coupled to a nuclear spin bath of arbitrary spin. Using a dynamical mean-field approach, we compute the nuclear spin polarization distribution with and without the quadrupolar coupling. We find that while hyperfine interactions drive dynamic nuclear polarization and mode-locking, quadrupolar couplings counteract these effects. The tension between these mechanisms is imprinted on the steady-state electron spin evolution, providing a way to measure the importance of quadrupolar interactions in a quantum dot. Our results show that higher-spin effects such as quadrupolar interactions can have a significant impact on the generation of dynamic nuclear polarization and how it influences the electron spin evolution.
