权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Quasi-particle scattering with polarized nuclei on ion cluster in liquid ^3He

液体中离子簇上极化核的准粒子散射^3He

基本信息

批准号：
10440102
负责人：
ISHIMOTO Hidehiko
金额：
$ 3.01万
依托单位：
University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1998
资助国家：
日本
起止时间：
1998 至 2000
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-10440102/
关键词：
liquid3^He Kondo effect snowball mobility quasi-particle exchange scattering cluster electron bubble フェルミ液体

项目摘要

Ion in liquid ^3He has a different structure depending on its sign of the charge. A positive ion, so called a "snowball", has localized ^3He spins on the surface. On the contrary a negative ion is a bubble in which an electron is trapped. Ion mobility at low temperatures below 100 mK is determined by scattering with Landau quasi-particles, hence the situation resembles an impurity scattering in metals. In the case of positive ion, the exchange scattering of localized ^3He spins on the ion surface with quasi particles seems to play an important role. To investigate such an effect, positive ion mobility in normal liquid. ^3He has been measured as a function of external magnetic fields up to 15 T at temperatures down to 3 mK. It does depend on the magnetic field at high pressures above 20 bars. Especially at 3.2 mK, it has a pressure dependent small and broad peak followed by a drastic decrease of about 30 % with increasing the field. On the other hand, at 20 mK, a monotonous decrease with increasing the magnetic field has been observed in the same pressure region. In contrast negative ion mobility at 29 bar is found to be independent of both temperature and magnetic field. These facts indicate that there exists an exchange interaction between ^3He quasi-particle and "snowball". However the results are too complicated for us to clarify the mechanism at present. Further systematic experiments should be made in the wide range of parameters, and a new theoretical treatment is eagerly desired to understand the positive ion mobility under high magnetic fields.

液体中的离子^3He有不同的结构，这取决于它的电荷符号。一个正离子，也就是所谓的“雪球”，在表面有局域化的^3He旋转。相反，负离子是一个电子被困在里面的气泡。离子在低于100 mK的低温下的迁移率是由朗道准粒子散射决定的，因此这种情况类似于金属中的杂质散射。在正离子中，定域^3He自旋在离子表面与准粒子的交换散射似乎起着重要的作用。为了研究这种效应，我们研究了正离子在正常液体中的迁移率。^3He已被测量为温度低至3mk时高达15t的外部磁场的函数。它确实取决于20巴以上高压下的磁场。特别是在3.2 mK时，它有一个与压力相关的小而宽的峰值，随后随着场的增加而急剧下降约30%。另一方面，在20 mK时，在相同的压力区域内，随磁场的增加出现单调的减小。相反，29巴时负离子迁移率与温度和磁场无关。这些事实表明，^3He准粒子与“雪球”之间存在交换相互作用。然而，结果过于复杂，目前我们还无法明确其机制。进一步的系统实验需要在更大的参数范围内进行，并迫切需要一种新的理论处理来理解高磁场下正离子的迁移率。