Quantum Gases in an Optical Superlattice

近年来，各种发明和创新使得在极低温度下产生原子的稀释气体成为可能，这基本上是已知宇宙中最冷的物质。 通过降低这些气体的温度，人们可以减少它们的无序性，从而实现两个令人兴奋的科学前景。 首先，低无序意味着在影响原子气体的条件下进行的测量-例如电场和磁场，或加速度和旋转-将具有非常小的噪声，允许更精确的测量。 第二，原子气体可以被操纵，使得气体中原子之间的相互作用类似于固体材料中电子之间的相互作用。 通过这种模拟，人们可以研究材料已经被预测表现出的性质，但由于真实的材料的过度无序和温度而被掩盖。 该项目通过向这两个前景迈进来促进科学和技术的进步。 主要和共同研究者，沿着与研究生和博士后，将开发技术，允许精确测量和原子气体。 研究人员还将研究模拟复杂材料磁性的原子气体的性质，这将有助于理解材料和设备中的磁性，这些材料和设备是当今（和未来）信息技术的基础。 青年科学家在这项工作中的核心参与，包括一些来自传统上在物理科学中代表性不足的群体的科学家，直接促进了美国多元化科学劳动力的培训。这个项目的重点是铷和钾原子的冷气体的行为，这些冷气体在空间周期性强度图案内移动，这些空间周期性强度图案是在几个相干光束的交叉点处产生的，光 光学图案产生空间周期性势，其类似于电子在固态材料中移动的晶体势。 光学组态可以快速调整，导致原子气体中的各种动力学。 这种动力学，这是本调查的主题，允许相干控制的原子运动的光学潜力（相关的精密测量，通过物质波干涉），也揭示了材料的性质，其中晶体结构往往会抑制秩序和运输（几何挫折，相关的材料科学）。 为了提高测量这种动力学的能力，该项目还研究了如何将计算成像方法（通过计算方法改进成像）导入原子气体的研究。 最后，自旋动力学作为一种工具来测量原子如何扩散在复杂的光学电位，通过磁共振成像中使用的方法的适应，并隔离几何挫折对原子运动的影响。

In recent years, various inventions and innovations have made it possible to produce dilute gases of atoms at extremely low temperature, essentially the coldest matter in the known Universe. By reducing the temperature of these gases, one reduces their disorder, allowing for two exciting scientific prospects. First, the low disorder implies that measurements made on conditions that effect the atomic gas--such as electric and magnetic field, or acceleration and rotation--will have very little noise, allowing for more precise measurements. Second, the atomic gas can be manipulated in a way that the interactions between atoms in the gas is similar to the interactions between electrons in a solid material. Through such mimicry, one can investigate properties that materials have been predicted to exhibit, but that have been obscured due to the excess disorder and temperature of real materials. This project promotes the progress of science and technology by advancing toward both these prospects. The principal and co-investigator, along with graduate students and postdocs, will develop techniques that allow for precise measurements with and of atomic gases. The researchers will also investigate properties of atomic gases that mimic the magnetic properties of complex materials, contributing in general to the understanding of magnetism in materials and devices that underlie so much of today's (and tomorrow's) information technology. The central involvement of young scientists in this work, including several from groups that have been traditionally underrepresented in the physical sciences, directly contributions toward the training of a diverse scientific workforce in the United States.Specifically, this project focuses on the behavior of cold gases of rubidium and potassium atoms that move within the spatially periodic intensity pattern generated at the intersection of several coherent beams of light. The optical pattern generates a spatially periodic potential that resembles the crystal potential in which electrons move in solid-state materials. The optical configuration can be rapidly tuned, resulting in various dynamics within the atomic gas. Such dynamics, which are the subject of the present investigation, allow for coherent control of atomic motion within the optical potential (relevant to precision measurements through matter-wave interferometry) and also reveal properties of materials in which the crystal structure tends to inhibit order and transport (geometric frustration, relevant to materials science). To improve one's ability to measure such dynamics, this project also investigates how methods of computational imaging (the improvement of imaging through computational methods) may be imported to the study of atomic gases. Finally, spin dynamics are used as a tool to measure how atoms diffuse within complex optical potentials, through an adaptation of methods used in magnetic resonance imaging, and also to isolate the effects of geometric frustration on atomic motion.