Time-Dependent Hydrodynamics in Uniform Fermi Gases

超冷原子气体可用于可控地探索与原子物理学之外的许多领域相关的物理概念。 该项目将在一个新的量子系统中探索时间相关的流体流动，该系统包括一个完全由激光制成的“光学盒”中的超冷原子气体。在这些桌面实验中使用的原子将被控制为相互吸引或排斥，以模拟自然界中的奇异量子系统。在这个系统中的测量将影响大爆炸后存在的近乎完美的流体流动理论，以及新材料的理论，例如远高于室温的超高温超导体。后者可能有一天会使节能电力线和磁悬浮列车成为可能。学生和博士后研究生将设计新的光学系统、新的计算机控制和机械系统，并研究电动力学和量子力学，广泛培训他们应对科学和技术方面的挑战。PI、博士后研究生和研究生将研究被困在“光学盒”中的6Li原子的均匀密度费米气体。将使用一个微阵列来投射一个动态控制的光学扰动，该扰动产生一个静态的正弦密度分布。流体动力学传输特性，如剪切粘度和热导率，将直接从扰动消失后的正弦密度分布的随时间变化的演变测量。 由于密度、温度、自旋组成和相互作用强度可控，这些实验为探索跨学科界限的概念提供了新的机会，包括对正常和超流体强相互作用量子流体中输运性质的独立测量，以及对最近共形场论对相互作用尺度预测的新测试，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。

Gasses of ultracold atoms can be used to controllably explore physics concepts relevant in many fields beyond that of atomic physics. This project will explore time-dependent fluid flow in a new designer quantum system, comprising an ultracold gas of atoms confined in an “optical box” made entirely of laser light. The atoms used in these tabletop experiments will be controlled to attract or repel each other as weakly or as strongly as desired to simulate exotic quantum systems in nature. Measurements in this system will impact theories of nearly perfect fluid flow, which existed just after the Big Bang, and theories of new materials, such as super-high temperature superconductors that operate far above room temperature. The latter may one day enable energy-saving power lines and magnetically levitated trains. Students and post-doctoral associates will design new optical systems, new computer control and mechanical systems, and study electrodynamics and quantum mechanics, broadly training them for challenges arising in science and technology.The PI, post-doctoral associate and graduate students will study uniform density Fermi gases of 6Li atoms, trapped in the “optical box.” A micromirror array will be used to project a dynamically controlled optical perturbation that creates a static, sinusoidal density profile. Hydrodynamic transport properties, such as the shear viscosity and thermal conductivity, will be measured directly from the time-dependent evolution of the sinusoidal density profile after the perturbation is extinguished. With controllable density, temperature, spin composition and interaction strength, these experiments offer new opportunities to explore concepts that cross interdisciplinary boundaries, including independent measurement of transport properties in normal and super fluid strongly interacting quantum fluids and new tests of recent conformal field theory predictions for interacting scale-invariant systems.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.