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

EAGER：非常规奇奇偶校验超导体常态高场和高应变的超声研究

• 批准号: 2016909
• 负责人: Bellave Shivaram
• 金额: $ 19.96万
• 依托单位: University of Virginia Main Campus
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-04-01 至 2024-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2016909&HistoricalAwards=false
• 关键词: EAGER; Ultrasound; Studies; Fields; Strain

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.

新材料正在推动进步，这将彻底改变从标准到量子计算的许多领域。 一种特别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，在正常状态和超导状态下都具有几种新特性，使其成为新应用的理想平台。 这种关联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。掌握不同量子相位的控制是开发这种高回报新技术的一个组成部分。这项研究将使用高磁场中的声速测量，并应用单轴压力来定位各种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对当地学校和博物馆的外展活动。技术摘要这个奖项是在非常高的磁场和高压下，单轴应用于重电子系统UPt3的实验工作。 这是一种独特的金属，在其超导（SC）中以及在正常磁状态下表现出多相。 在UPt3中，已知存在微小的三角畸变，即偏离其标称的六方晶体对称性。 这种对称性破缺效应在强关联电子系统（SCES）的许多族中是相当普遍的。 多个状态，如电荷（CDW）和自旋（SDW）密度波，非常规超导性和新的磁相可以共存于SCES和精确控制的实验需要梳理出各种物理相互作用。通过高磁场和大的单轴应力的组合应用，PI建议对UPt3中的破缺晶体对称性进行精细调谐。 这样一个联合应用的两个非常大的外部领域，磁场和压力，迄今为止从未被采用，因此，拟议的工作是危险的。 不同的磁相以及它们在同时施加高磁场和高压下如何演变将通过测量超声波穿过UPt3晶体的速度来研究。 声速是衡量电子在不同磁相和超导相中行为的一个非常敏感的指标。该奖项反映了NSF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。