Quantum Engineering with Dissipation

在题为“量子工程与耗散”的项目中，我们创建和研究强相互作用的量子简并原子气体，重点是由强非弹性或耗散相互作用引起相关性的系统。耗散正在成为量子工程的一种新工具，用于创造具有根本意义的新状态。我们使用耗散在三维光学晶格中的锶凝聚体中创建空间相关性，并研究超流到莫特绝缘体转变的耗散模拟。光学Feshbach共振被用来产生两体非弹性相互作用，而三体非弹性相互作用的影响可以用Sr-86来探索，它自然具有很大的三体衰变率。在这些系统中有许多有趣的性质需要研究，例如创建粒子相关性的标准，激发光谱，以及改变晶格和相互作用参数的绝热性时间尺度。此外，在一个散装系统中，我们将看看玻色凝聚的相互作用强度从弱相互作用到强相互作用制度，这可以产生与光学Feshbach共振的快速淬火的响应。在体系统和晶格中的实验中，感兴趣的是多体状态下空间相关性发展的时间尺度。当大量粒子聚集在一起并相互作用时，可能会出现新的现象，这些现象是粒子对之间相互作用的基本形式所无法预料的。超导就是一个著名的例子。 理解强相互作用的多体系统对物理学的许多领域来说都是一个巨大的挑战，因为新的材料特性具有技术意义，也因为系统可能非常复杂，它们扩展了我们对自然世界的理解。 在过去的十年中，在创造和研究气体原子的超冷云方面取得了巨大的进展，这些气体原子被激光冷却到绝对零度以上百万分之一度左右的温度。以这种方式制造的超冷原子具有惊人的特性，即它们的相互作用可以任意控制，这为使用它们来制造设计材料或测试相互作用的多体系统模型提供了可能性。在美国国家科学基金会的资助下，美国德克萨斯州休斯敦莱斯大学的基利安教授的研究小组将开发利用激光操纵原子-原子相互作用的新技术，并寻找新的涌现现象。这项工作将涉及至少两名研究生和一名本科生，并将培养他们从事光学或材料方面的高科技职业。这项工作还将涉及本科研究人员在夏季研究和工作期间的学术术语导致荣誉研究论文。诸如此类的基本原子物理学实验为今天的技术奇迹奠定了科学和人力资源基础。

In the project entitled "Quantum Engineering with Dissipation," we create and study strongly interacting quantum degenerate atomic gases, with a focus on systems in which correlations are induced by strong inelastic, or dissipative, interactions. Dissipation is emerging as a new tool for quantum engineering for creating novel states of fundamental interest. We use dissipation to create spatial correlations in strontium condensates in three-dimensional optical lattices and study the dissipative analog of the superfluid-to-Mott-insulator transition. An optical Feshbach resonance is used to create two-body inelastic interactions, and the effects of three-body inelastic interactions can be explored with Sr-86, which naturally has a large three-body decay rate. There are many interesting properties to study in these systems, such as the criteria for creation of particle correlations, excitation spectra, and adiabaticity timescales for changing lattice and interaction parameters. In addition, in a bulk system we will look at the response of a Bose condensate to a rapid quench of the interaction strength from the weakly interacting to the strongly interacting regime, which can be produced with an optical Feshbach resonance. Of interest to experiments in a bulk system and lattice is the timescale for development of spatial correlations in the many-body state.When large numbers of particles come together and interact, new phenomena can emerge that are unexpected from the basic form of the interaction between pairs of particles. Superconductivity is a famous example of this. Understanding strongly interacting, many-body systems is a grand challenge for many areas of physics because of the promise of new material properties of technological significance and also because the systems can be very complicated and they stretch our understanding of the natural world. In the last decade, there have been great advances in the creation and study of ultracold clouds of gaseous atoms, which are cooled by lasers to temperatures around a millionth of a degree above absolute zero. Ultracold atoms made in this way have the amazing property that their interactions can be arbitrarily controlled, which opens the possibility of using them to make designer materials or test models of interacting, many-body systems. With the support of this National Science Foundation grant, Prof. Killian's research group at Rice University in Houston, Texas will develop new techniques for manipulating atom-atom interactions using lasers and search for new emergent phenomena.This work will involve at least two graduate students and one undergraduate student, and it will train them for high-technology careers in optics or materials. This work will also involve undergraduate researchers in summer research and work during the academic terms leading to honors research theses. Basic atomic physics experiments such as these lay the scientific and human resources foundation today for the technological marvels of tomorrow.