Experimental Studies at Ultralow Temperatures

超低温实验研究

• 批准号: 9623716
• 负责人: Hans Bozler
• 金额: $ 34万
• 依托单位: University of Southern California
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1996
• 资助国家: 美国
• 起止时间: 1996-09-15 至 1999-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9623716&HistoricalAwards=false
• 关键词: Experimental; Studies; Ultralow; Temperatures

9623716 Bozler This project is an investigation of three different materials at ultralow temperatures while developing advanced dc SQUID amplifiers to support this work. The first study is of the magnetic properties of superfluid 3He, focusing on the discrepancy between SQUID and NMR measurements of the static susceptibility. The second study is of thin films of 3He in magnetic fields sufficiently small that a wo-dimensional nuclear ferromagnetic transition can be manifested. In these magnetic fields, conventional NMR techniques are unusable. Finally, electrical conduction in reduced dimensionality systems will be studied, including the physics of disorder in artificial two-dimensional networks of effectively one-dimensional wires. %%% This project is a study of materials at ultralow temperatures combined with, and supported by, the development of ultralow temperature experimental techniques, including advanced low-noise amplifiers. At temperatures near 1 mK (0.001 degrees above Absolute Zero) the rare isotope of helium (helium-3) changes to a superfluid whose magnetic properties are not yet well understood. These magnetic properties will be studied in this project. Thin films of liquid helium-3 will also be studied because they have proved to be an excellent model for magnetism in two dimensions. Artificial one- and two-dimensional metallic systems will be manufactured and studied to better understand the role of disorder in natural physical systems. ***

小行星9623716 这 该项目是对三个 在超低温下使用不同的材料，同时开发先进的直流SQUID放大器来支持这项工作。第一项研究是超流3He的磁性，重点是静态磁化率的SQUID和NMR测量之间的差异。第二项研究是3He薄膜 在 磁场足够 小 的 二维核铁磁转变可以 表现出来。 在这些磁场中，常规的NMR技术是不可用的。最后，将研究降维系统中的电传导，包括 物理学的无序在人工二维网络的有效一维线。 %这个 项目 是一项研究材料 在 超低温 组合 并且 支持 通过， 开发超低温实验技术，包括先进的低噪声放大器。 在接近1 mK（绝对零度以上0.001度）的温度下，氦的稀有同位素（氦-3）变成超流体，其磁性尚未得到很好的理解。 本项目将研究这些磁性。 液氦-3薄膜也将被研究，因为它们已被证明是二维磁性的极好模型。 人工一维和二维金属系统 将进行制造和研究 到 更好地理解自然物理系统中无序的作用。 ***