CAREER: Developing Hybrid Quantum Systems Using Superconducting Circuits

*技术摘要*这个项目寻求研究腔量子电动力学、多体动力学以及最终的量子信息，使用漂浮在超流氦上方的电子。氦上的电子形成一种独特的二维电子气，通过零点运动悬浮在超流体表面上方。它异常干净，具有已知的最高迁移率，据预测具有长自旋相干性，但尽管它已经被研究了很多年，人们对单个电子的性质知之甚少。该项目将使用超导传输线空腔相干地耦合到第一个系综，并最终耦合到单个被捕获的电子。计算预测，氦上单电子的电荷和自旋动力学都有很长的相干时间，但这将是第一次实验测量。由于超导电路技术的最新进展，这些实验现在才有可能。该项目将支持博士生在这些先进技术方面的教育，从历史上看，这对从学术界到我们最先进的技术行业的许多科学职业来说都是极好的培训。这项结合多量子相干系统的研究有望引起科学界的广泛兴趣，并为其他领域的努力提供模板。*非技术摘要*当电子喷洒到绝缘液体的表面时，它们会粘在表面上。令人惊讶的是，在绝对零度以上几度的低温下，由于量子力学效应，它们开始漂浮在表面上几纳米的高度。当处理原子或粒子时，最大的技术挑战是将它们捕获在真空中，但在这个特殊的系统中，电子自然漂浮，就像海洋上的微型浮标。因为它们是悬浮的，所以它们具有原始的特性，但像浮标一样，它们也与下面流体中的波有复杂的相互作用。该项目将继续进行实验，以分离漂浮在氦上的单电子，并探索它们与光、超流体波以及彼此之间的复杂相互作用。这将通过使用最先进的实验科学工具来实现：纳米制造、超低温物理和量子计算电子器件。该项目将支持博士生在这些先进技术方面的教育，从历史上看，这对从学术界到我们最先进的技术行业的许多科学职业来说都是极好的培训。这些研究将促进我们对这一迷人系统的理解，并最终可能导致量子计算机，其中的比特由单个电子存储，使用很少的功率，并以指数级加速重要的计算类别。

****TECHNICAL ABSTRACT****This project seeks to study cavity quantum electrodynamics, many-body dynamics, and eventually quantum information, using electrons floating above superfluid helium. Electrons on helium form a unique two-dimensional electron gas levitated by zero-point motion above the superfluid surface. It is exceptionally clean, having the highest known mobility, and is predicted to have long spin coherence, but while it has been studied for many years, little is known about the properties of individual electrons. This project will use superconducting transmission line cavities coherently coupled to first ensembles, and eventually individual trapped electrons. Calculations predict that both the charge and spin dynamics of single electrons on helium possess long coherence times, but these will be the first experimental measurements. These experiments are only possible now because of recent advances in superconducting circuit technology. This project will support the education of a PhD student in these advanced technologies, which has historically shown itself to be excellent training for many scientific careers from academia to our most advanced technology industries. This research combining multiple quantum coherent systems is expected to be of broad interest to the scientific community, and serve as a template for efforts in other fields.****NON-TECHNICAL ABSTRACT****When electrons are sprayed onto the surface of an insulating liquid, they stick to the surface. Amazingly, at low temperatures, just a few degrees above absolute zero, they begin to levitate a few nanometers above the surface due to quantum mechanical effects. When working with atoms or particles, most of the technical challenge is in trapping them in vacuum, but in this special system, the electrons naturally float, like microscopic buoys on the ocean. Because they are levitated, they have pristine properties, but like buoys, they also have complex interactions with waves in the fluid below. This project will pursue experiments to isolate single electrons floating on helium, and probe their complex interactions with light, superfluid waves, and each other. This will be accomplished by employing the most advanced tools of experimental science: nanofabrication, ultra-low temperature physics, and quantum computing electronic devices. This project will support the education of a PhD student in these advanced technologies, which has historically shown itself to be excellent training for many scientific careers from academia to our most advanced technology industries. These studies will advance our understanding of this fascinating system and eventually could lead to quantum computers in which bits are stored by individual electrons, using little power and exponentially speeding important classes of computations.