EAGER: Ultrasound Studies in High Fields and High Strain of the Normal State in Unconventional Odd Parity Superconductors

新材料正在推动从标准计算到量子计算等许多领域的革命。一种特别令人感兴趣的材料是非常规超导体。这些材料通常被描述为强相关电子系统，在正常和超导状态下具有几种新特性，使其成为新应用的理想平台。这种相关性可以使电子表现出新的效应，如手性，即手性和向列性或取向顺序。这些新颖的电子效应可以在新的量子技术中用于计算和安全通信。掌握对不同量子相的控制是开发这种高回报新技术的重要组成部分。本研究将利用声速测量和单轴压力在高磁场下定位不同磁相并研究它们如何演变。该项目还将支持学生参与研究以及在当地学校和博物馆开展外展活动。技术摘要：本奖项是奖励在单轴高磁场高压下，在重电子系统UPt3上所做的实验工作。这是一种独特的金属，它在超导（SC）和正常磁性状态下都表现出多相。在UPt3中，一分钟的三角畸变，即偏离其标称的六方晶体对称是已知存在的。这种对称性破缺效应在许多强相关电子系统（SCES）族中是相当普遍的。电荷（CDW）和自旋（SDW）密度波、非常规超导和新型磁相等多种状态可以在ses中共存，需要精确控制的实验来梳理各种物理相互作用。通过高磁场和大单轴应力的联合应用，PI提出了精细调谐UPt3中破碎的晶体对称性。迄今为止，从未采用过这样的两个非常大的外部磁场，即磁场和压力的联合应用，因此拟议的工作是危险的。通过测量超声波通过UPt3晶体的速度，研究不同磁相及其在高磁场和高压同时作用下的演变。声速是测量电子在不同磁相和SC相中的行为的一种非常灵敏的方法。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Non-technical AbstractNew materials are driving advances that will revolutionize many areas ranging from standard to quantum computing. One type of material of particular interest are unconventional superconductors. These materials, which are often described as strongly correlated electronic systems, have several novel properties in both their normal and superconducting state that make them a desirable platform for new applications. Such correlations can make the electrons exhibit novel effects such as chirality i.e. handedness and nematicity or orientational order. These novel electronic effects can be exploited in new quantum technologies for computing and secure communication. Mastering the control of different quantum phases is an integral part in the development of such high pay-off new technologies. This research will use velocity of sound measurements in high magnetic fields and with the application of uniaxial pressure to locate the various magnetic phases and study how they evolve. The project will also support the involvement of students in research as well as outreach activities to local schools and museums.Technical AbstractThis award is for experimental work in very high magnetic fields and high pressures, applied uniaxially, on the heavy electron system UPt3. This is a unique metal which exhibits multiple phases in its superconducting (SC) as well in the normal magnetic states. In UPt3 a minute trigonal distortion, i.e. a departure from its nominal hexagonal crystal symmetry is known to exist. Such symmetry breaking effects are quite general in many families of strongly correlated electronic systems (SCES). Multiple states such as charge (CDW) and spin (SDW) density waves, unconventional superconductivity and novel magnetic phases can coexist in SCES and precisely controlled experiments are needed to tease out the various physical interactions. Through a combined application of high magnetic fields and large uniaxial stress the PI proposes to delicately tune the broken crystal symmetry in UPt3. Such a conjoint application of two very large external fields, magnetic and pressure, has hitherto never been employed and hence the proposed work is risky. The different magnetic phases and how they evolve under simultaneous application of high magnetic fields and high pressure will be studied by measuring the velocity of ultrasound passing through crystals of UPt3. Sound velocity is a very sensitive measure of how electrons in the different magnetic and SC phases behave.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.