Collective Modes in Superfluid Fermi Systems

9309061 Ketterson本项目致力于研究凝聚态系统的序参量集体模式，主要是超流体3He和超导UPt3。超流体3已知他有一个非常规的超流体序参量，越来越多的证据表明UPt3也是如此。该项目将继续研究超流体3He中的集体模式现象，特别强调剪切波传播和电场效应分裂。首席研究员预测，利用超声波衰减或电磁吸收，可以为UPt3的序参量集体模式制造许多集体模式（不仅仅是核磁共振）。他们的观察将确立这种现象在超导体中是否存在（这一话题自传统超导体理论发展以来一直存在争议），并为他们在传统超导体中观察开辟了道路。量子系统表现出复杂的波动或振动行为，可以通过发送声波或磁化波来探测。类似的技术可以用来探测系统的磁性、超流体或超导程度。该项目利用新颖的声学和其他手段研究一种特殊的超流体3He和一种所谓的非常规超导体UPt3。这些实验将揭示为什么所有超导体都不一样，并将提供对实际超导体、高tc超导体和其他包括液体、固体、原子核甚至中子星在内的复杂组合感兴趣的基本信息。＊＊＊

9309061 Ketterson This project is devoted to the study of the order parameter collective modes in the condensed matter systems, principally superfluid 3He and superconducting UPt3. Superfluid 3He is known to have an unconventional superfluid order parameter and there is growing evidence that the same is true of UPt3. This project will continue investigations of collective mode phenomena in superfluid 3He with special emphasis on shear wave propagation and electric field effect splittings. A prediction by the principal investigator, that many collective modes (not just nmr) can be made for the order parameter collective modes in UPt3 using ultrasonic attenuation or electromagnetic absorption. Their observation would establish the existence if this phenomena in a superconductor (a topic that has long been debated since the development of conventional superconductor theory) and could open the way to their observation in conventional superconductors. %%% Quantum systems exhibit complex wave or Vibrational behavior which can be probed by sending sound waves or magnetization waves through them. Similar techniques can be used to probe the degree to which a system is magnetic or superfluid or superconducting. This project uses novel acoustic and other means to study a special superfluid 3He and a so-called unconventional superconductor, UPt3. The experiments will shed light on why all superconductors are not the same, and will provide fundamental information that will be of interest in practical superconductors, the high-Tc superconductors, and other complex assemblies which include liquids, solids, nuclei and even neutron stars. ***