Exploring the Properties of Quantum Many-Body Scar States in Dipolar Gases

探索偶极气体中量子多体疤痕态的性质

• 批准号: 2308540
• 负责人: Benjamin Lev
• 金额: $ 75.5万
• 依托单位: Stanford University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2027-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2308540&HistoricalAwards=false
• 关键词: Exploring; Properties; Quantum; Many; Body

The PI and graduate students recently discovered a quantum version of the famous Archimedes screw. Known from antiquity as a device to transport water (or grain) up elevations, the device relies on the “chiral” property of the screw: Rotating it moves water in one direction even though the screw periodically returns to its same orientation. The group’s quantum Archimedes screw consists of atoms confined into a one-dimensional tube of light. Increasing a magnetic field “turns” the screw by causing the atoms to scatter from each other with periodically increasing and decreasing probabilities. This serves to pump the atoms’ energy to higher and higher levels, just like the traditional screw can pump water up to great heights. In the past, when this was attempted with non-magnetic atoms, the screw collapsed---the atoms fell out of the light tube by forming unwanted molecular states. However, the PI and graduate students recently discovered that atoms that are strongly magnetic and set to repel each other do not form these molecules. That allowed the research group to complete these topological pumping cycles for the first time and reach so-called “quantum many-body scar states” for the first time. This research program will explore the properties of these scar states, which are atypical, highly excited non-thermal states of quantum matter. Specifically, their momentum distributions will be measured to better understand the nature of the correlations between the atoms when in these states of matter. The PI and graduate students will also rapidly compress these gases to observe their response to extreme conditions, which is often a good way to learn more about a quantum state of matter. Investigating such states can teach us about new ways in which quantum matter may exist away from regimes of ultralow temperatures. This knowledge helps guide the group toward methods to protect and store quantum information for use in a quantum computer or sensing device. This project will serve as an excellent training ground for the next generation of quantum engineers. Moreover, the PI will start a chapter of the Warrior-Scholar Project for the first time at Stanford to better integrate our diverse and talented veteran population into programs of higher education. The PI and graduate students will capitalize on their discovery of a new type of quantum many-body scar state in topologically pumped, dipolar-stabilized 1D gases of dysprosium. The research group plans to extend the frontier of quantum simulation by using a unique experimental system to explore the novel properties of these scar states, both in and out of equilibrium. Nearly integrable systems do not immediately relax to thermal equilibrium, but can persist in highly non- thermal (prethermal) steady states, characterized by the “rapidities” of emergent quasiparticle excitations. In strongly interacting integrable systems, the rapidity distribution of quasiparticles can behave differently from the momentum distribution of the microscopic particles. This research group has gained the experimental capability to measure the rapidity distributions of 1D dipolar quantum gases. The PI and graduate students will conduct a program to utilize both momentum and rapidity distribution measurements to explore the properties of these dipolar quantum many-body scar states, both in steady state and quenched far away from equilibrium.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.

PI和研究生最近发现了著名的Archimedes螺丝的量子版本。该设备从上古时期作为一种运输水（或谷物）向上运输水（或谷物）的装置，依赖于螺钉的“手性”特性：旋转它仍会向一个方向移动水，即使螺钉定期返回相同的方向。该小组的量子阿基梅德螺钉由限制在一维光管中的原子组成。通过导致原子彼此散射，随着可能性的增加和减少的可能性，增加磁场“转动”螺钉。就像传统螺钉可以将水泵送到高度一样，这可以将原子的能量泵送到更高的水平。过去，当尝试使用非磁性原子进行尝试时，螺钉塌陷了 - - 原子通过形成不良的分子状态从轻型管中掉下来。但是，PI和研究生最近发现，强烈磁性并互相排斥的原子不会形成这些分子。这使研究小组首次完成了这些拓扑抽水循环，并首次达到所谓的“量子多体疤痕状态”。该研究计划将探索这些疤痕状态的特性，这些疤痕状态是量子问题的非典型，高度激发的非热状态。具体而言，将测量它们的动量分布，以更好地理解物质状态时原子之间相关性的性质。 PI和研究生还将迅速压缩这些气体以观察它们对极端条件的反应，这通常是了解有关物质量子状态的好方法。调查此类州可以教我们有关量子问题可能存在于超高温政权的新方法。这些知识有助于指导小组采用保护和存储量子信息以在量子计算机或灵敏度设备中使用的方法。该项目将成为下一代量子工程师的绝佳训练场。此外，PI将首次在斯坦福大学开始宣战项目的一章，以更好地将我们的潜水员和才华横溢的退伍军人人口融入高等教育计划。 PI和研究生将利用他们在拓扑泵送的，偶尔稳定的1D气体疾病中发现了一种新型的量子多体疤痕状态。研究小组计划通过使用独特的实验系统来探索这些疤痕状态的新型特性，无论是在同等繁殖的情况下，都可以扩展量子模拟的前沿。几乎可集成的系统不会立即放松到热相等，而是可以持续在高度非热（prethermal）的稳态中，其特征在于新兴的准粒子兴奋的“速度”。在强烈相互作用的集成系统中，准颗粒的速度分布与微观颗粒的动量分布的行为不同。该研究小组已获得实验能力，以测量1D偶极量子气体的速度分布。 The PI and graduate students will conduct a program to utilize both momentum and rapidity distribution measurements to explore the properties of these dipolar quantum many-body scar states, both in steady state and quenched far away from equilibrium.This award reflects NSF's statutory mission and has been deemed honestly of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.