US-France Cooperative Research: Nuclear Spin Dynamics in Solid and Liquid Helium Three

该奖项将支持佛罗里达大学的普拉迪普·库马尔博士和法国奥赛物理实验室的莫里斯·查佩利耶博士之间的合作研究。研究人员建议研究量子流体或固体中的核自旋动力学。具体地说，研究将集中在以下三个问题上：(1)极化纯液和稀液。研究人员计划研究自旋晶格_弛豫时间t1，并区分体相和各种表面机制的作用。他们还将研究粘度和声音衰减作为偏振的函数。(2)固/液界面：主要问题包括_靠近壁面的固体和液体的精确性质对这些问题有至关重要的影响，也将被研究。(3)低密度固体氦_研究人员建议对反常磁化率进行精确的研究，以检验极化子模型，并研究空位引起的弛豫。美国和法国的调查人员都在量子流体和固体领域拥有丰富的研究经验，特别是液体和固体氦三。这项研究的结果将有助于理解量子液体和固体系统的性质，这对凝聚态物理具有基本的重要性。

This award will support cooperative research between Dr. Pradeep Kumar, University of Florida and Dr. Maurice Chapellier, Laboratoire de Physique des Solides, Orsay, France. The investigators propose to study the dynamics of nuclear spins in a quantum fluid or solid. Specifically, the research will focus on the following three problems: (1) Polarized pure and dilute __________________________ liquid. The investigators plan to study the spin-lattice ______ relaxation time T1 and distinguish between the role of bulk and various surface mechanisms. They will also investigate the viscosity and sound attenuation as a function of the polarization. (2) The solid/liquid interface: The principal problems include the __________________________ details of the crystallization process, as well as the transfer of magnetic energy across the interface. The precise nature of the solid and the liquid near a wall has a critical bearing on these questions and will also be studied. (3) Low density solid helium _________________________ three: In both bulk and constrained geometry, the investigators _____ propose a precision study of the anomalous susceptibility to test the polaron model and to investigate the relaxation induced by vacancies in general. Both the U.S. and French investigators have extensive research experience in the area of quantum fluids and solids, and in particular liquid and solid helium three. The results of this research will contribute to the understanding of the properties of quantum liquids and solids systems, which is of basic importance to condensed matter physics.