Spin Transport in Fermi Liquids and Porous Media

提案的第一部分继续了当前的一个项目：首先，使用自旋波技术，NMR将用于测量稀释3He-4He溶液中的自旋输运，以测试偏振量子气体的新理论。在第二个实验中，我们将使用振动丝粘度计直接测量极化对动量输运的影响。此外，将尝试创建核磁孤子，并使用核磁共振自旋扩散技术检测纯3He液体中假设的自旋波动。该提案的第二部分涉及在低温下限制在随机多孔材料中的量子液体的效应。首先，将使用3He-4He溶液在比室温下可能的更长长度尺度上探测随机几何形状。其次，将研究类似于在无序电子系统中看到的效应——随机孔隙空间内量子或自旋波干扰引起的电导波动和强弱局域化。

The first part of the proposal continues a current project: first, NMR will be used to measure spin transport in a dilute 3He-4He solution, using a spin-wave technique, in order to test a new theory for polarized quantum gases. In a second experiment, one will use a vibrating-wire viscometer to directly measure the effects of polarization upon momentum transport. In addition, attempts will be made to create nuclear magnetic solitons, and to detect hypothesized spin fluctuations in pure 3He liquid using an NMR spin-diffusion technique. The second part of the proposal deals with effects in a quantum liquid confined at low temperature in a random porous material. First, one will use a 3He-4He solution to probe random geometries over much longer length scales than is possible at room temperature. Secondly, a search will be made for effects analogous to those seen in disordered electronic systems -- conductance fluctuations and weak and strong localization resulting from quantum or spin-wave interference within the random pore space.