Electron and Nuclear Spin Interactions with Periodic Optical Pumping

非技术性描述：物质的基本组成部分是由电子和原子核组成的原子。电子具有可以流动的电荷，从而产生用于电子信息处理和存储的电流。电子和原子核具有另一种称为“自旋”的基本性质，可用于量子计算，并为电子学与磁数据存储的更有效集成提供了途径。该项目使用短光脉冲来研究电子的自旋和半导体材料的原子核。目标是了解如何利用周期性光泵浦来控制核自旋。了解电子和核自旋的行为和相互作用有助于新技术的发展，这些技术可以导致更快，更有效的信息处理，更强大的量子信息处理和通信平台，以及改进的磁共振成像。该研究还为学生提供了半导体物理，最先进的光学测量，数据采集和分析以及数值建模方面的宝贵培训。毕业生准备在半导体和光子学行业从事职业。该项目研究了周期性电子自旋泵浦对半导体中动态核极化的影响，目的是提高对耦合电子-核自旋系统的理解，以及它如何受到材料参数，外加磁场和光的影响。控制电子和核自旋之间的相互作用对于基于自旋的量子信息处理、量子通信和磁共振成像具有重要意义。核自旋去极化时间通常超过电子自旋寿命几个数量级，提供了一种在更长时间尺度上存储信息的方法。此外，核自旋涨落可以限制局域电子的电子自旋相干时间，因此开发减少核自旋涨落影响的方法可以提高电子自旋相干时间。该研究利用光学泵浦-探测测量技术和数值模拟来研究动态核自旋极化现象，包括核诱导频率聚焦，并旨在使用设计的局部脉冲序列来产生和旋转电子自旋极化，从而更精确地控制核自旋系统。该项目为学生在半导体物理、光谱学和数值模拟方面的培训提供了令人兴奋的机会。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Non-Technical Description:The basic building block of matter is the atom which is made of electrons and the nucleus. Electrons have charges which can be made to flow, creating electric currents used in information processing and storage in electronics. Electrons and nuclei possess another fundamental property called “spin”, which can be utilized for quantum computing and offers a pathway for the more efficient integration of electronics with magnetic data storage. This project uses short light pulses to study the spins of electrons and the nuclei of semiconductor materials. The goal is to gain understanding of how periodic optical pumping can be used to control the nuclear spins. Understanding how electron and nuclear spins behave and interact contributes to the development of new technologies that could lead to faster and more efficient information processing, more robust platforms for quantum information processing and communication, and improved magnetic resonance imaging. The research also provides valuable training to students in semiconductor physics, state-of-the-art optical measurements, data acquisition and analysis, and numerical modeling. Graduates are prepared to pursue careers in the semiconductor and photonics industries. Technical Description:The project investigates the effect of periodic electron spin pumping on dynamic nuclear polarization in semiconductors with the goal of improving understanding of the coupled electron-nuclear spin system and how it is affected by material parameters, applied magnetic field, and light. Controlling the interactions between electron and nuclear spins is of great interest for spin-based quantum information processing, quantum communication, and magnetic resonance imaging. The nuclear spin depolarization time typically exceeds the electron spin lifetime by several orders of magnitude, providing a way to store information over longer time scales. In addition, nuclear spin fluctuations can limit the electron spin coherence time for localized electrons, so developing methods to reduce the effects of nuclear spin fluctuations can enhance the electron spin coherence time. The research utilizes optical pump-probe measurement techniques and numerical modeling to study dynamic nuclear spin polarization phenomena, including nuclear-induced frequency focusing, and aims to enable ways to more precisely control the nuclear spin system using designed localized pulse sequences to generate and rotate electron spin polarization. The project provides exciting opportunities for student training in semiconductor physics, optical spectroscopy, and numerical modeling.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.