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

9971124 reppy这是一个凝聚态物理项目，研究氦-4薄膜中的玻色-爱因斯坦凝聚（BEC）。该项目是对最近在碱蒸气和自旋极化氢原子气体系统中进行的BEC演示的补充。多孔Vycor玻璃三维连接基板上吸附氦的稀释玻色气体状态的研究为捕获原子气体系统提供了有价值的替代方案。Vycor系统中的He-4允许访问大范围的粒子密度，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。最初的项目将是检查转变温度随密度增加的变化。参与该项目的研究生可以接触到令人兴奋的基础物理研究并体验最先进的仪器。它为各种各样的职业提供了优秀的培训。%%%这是一个凝聚态物理项目。玻色-爱因斯坦凝聚（BEC）现象在低密度原子气体中被限制在电磁阱中，在科学界引起了极大的兴奋。在这里提出的工作中，将研究一种替代BEC的方法，利用低密度吸附在多孔基板Vycor玻璃表面的4He原子。在非常低的温度下，原子的量子波长变得与移动原子之间的分离相当，并且发生了BEC现象。在4He-Vycor系统中进行BEC研究的一个真正优势是，粒子密度可以在整个范围内进行调整，从非常低的密度到高密度，可与散装超流氦相媲美。参与该项目的研究生可以接触到令人兴奋的基础物理研究并体验最先进的仪器。该学院为各种各样的职业提供优秀的培训

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.***