Quantum Fluids at Low Temperatures: 2D and Dilute Bose Gas Studies

低温量子流体：二维和稀玻色气体研究

• 批准号: 9971124
• 负责人: John Reppy
• 金额: --
• 依托单位: Cornell University
• 依托单位国家: 美国
• 项目类别: Continuing grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-06-01 至 2002-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9971124&HistoricalAwards=false
• 关键词: Quantum; Fluids; Low; Temperatures; 2D

9971124ReppyThis is a condensed matter physics project that is concerned with the Bose-Einstein condensation (BEC) in the context of films of Helium-4. The project is complementary to the recent demonstration of the BEC in the atomic gas systems of alkali vapor and spin polarized hydrogen. The study of the dilute Bose gas regime for helium adsorbed on the 3D connected substrate of porous Vycor glass provides a valuable alternative to the systems of trapped atomic gas. The He-4 in Vycor system allows access to a wide range of particle densities, ranging from the dilute Bose gas regime to the high-density, strongly-interacting regime, a regime that is currently inaccessible to the atomic gas systems. An initial project will be to examine the variation of transition temperature with increasing density. Graduate students participating in the project benefit from exposure to exciting fundamental physics research and experience with state-of-the-art instrumentation. The provides excellent training for a wide range of careers. %%%This is a condensed matter physics project. The demonstration of Bose Einstein Condensation (BEC) in low density atomic gases confined to electromagnetic traps has created great excitement in the scientific community. In the work proposed here, an alternative approach to BEC will be investigated utilizing 4He atoms adsorbed at low density on the surface of a porous substrate, Vycor glass. At very low temperatures the quantum wavelength of the atoms becomes comparable to the separation between the mobile atoms and the phenomena of BEC occurs. A real advantage to BEC studies in the 4He-Vycor system, is that the particle density can be tuned over the entire range from the very low density regime to high densities comparable to bulk superfluid helium. Graduate students participating in the project benefit from exposure to exciting fundamental physics research and experience with state-of-the-art instrumentation. The provides excellent training for a wide range of careers.***

9971124 Reppy这是一个凝聚态物理项目，关注氦-4薄膜中的玻色-爱因斯坦凝聚（BEC）。该项目是对最近在碱蒸汽和自旋极化氢原子气体系统中BEC演示的补充。研究氦在三维连通多孔玻璃基片上的稀玻色气体状态为囚禁原子气体系统提供了一种有价值的替代方案。 Vycor系统中的He-4允许访问广泛的粒子密度，从稀玻色气体状态到高密度，强相互作用状态，这是目前原子气体系统无法访问的状态。一个初步的项目将是研究转变温度随密度增加的变化。参与该项目的研究生将受益于令人兴奋的基础物理研究和最先进的仪器经验。该课程为各种职业提供了出色的培训。这是一个凝聚态物理项目。玻色-爱因斯坦凝聚（BEC）在低密度原子气体中被限制在电磁阱中的演示在科学界引起了极大的兴奋。在这里提出的工作中，BEC的替代方法将利用4 He原子吸附在多孔基板，Vycor玻璃的表面上的低密度进行研究。在非常低的温度下，原子的量子波长变得与移动的原子之间的间隔相当，并且发生BEC现象。在4 He-Vycor系统中进行BEC研究的一个真实的优点是，粒子密度可以在整个范围内从非常低的密度区域调整到与体超流氦相当的高密度。参与该项目的研究生将受益于令人兴奋的基础物理研究和最先进的仪器经验。为各种职业提供了良好的培训 *