LEAPS-MPS: Design and discovery of new magnetic Weyl semimetals

非技术摘要：电子技术的进步有赖于新型量子材料的发现和发展。最近发现的Weyl半金属是一类很有前途的新材料，具有潜在的广泛的技术应用。然而，目前已知的许多Weyl半金属需要施加外部磁场或压力来揭示其新颖的行为，这在无法应用的应用中是一个缺点。在这方面，新的本征磁性Weyl半金属是可取的，但只有少数这样的材料是已知的。该项目旨在通过单晶生长和磁电输运测量来探索和表征一类新的磁性Weyl半金属材料。它将解锁发现和设计新的磁性Weyl半金属所需的关键成分。该项目包括一个全面的推广战略，并为高中、本科生和研究生提供重要的材料合成和表征方面的培训。技术摘要：磁性Weyl半金属材料具有破碎的空间反转和时间反转对称，其准粒子激发是Weyl费米子，最近引起了人们的极大关注，因为它们显示了各种新的拓扑态，有望在不同的技术应用中，包括量子比特。尽管有大量的理论和实验工作，但只有几个这样的材料是已知的。该项目的目标是通过单晶生长和磁输运性质(即霍尔效应)的测量，通过研究磁性强相关金属间化合物家族来发现和设计这种材料。结合理论计算和角度分辨光电子能谱(ARPES)测量，该项目将提供对Weyl费米子如何在凝聚态系统中表现的更深入的洞察，通过发现许多新的磁性Weyl半金属家族来拓宽当前的研究领域，并研究Weyl费米子、电子-电子关联和量子临界之间的相互作用。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Non-technical abstract:Technological progress in electronics depend on the discovery and development of novel quantum materials. Recently discovered Weyl semimetals are a promising new class of materials with potentially wide-ranging technological applications. However, many of the currently known Weyl semimetals require the application of an external magnetic field or pressure to reveal their novel behavior, which is a drawback in applications where none can be applied. In that respect, new intrinsically magnetic Weyl semimetals are desirable, but only a few such materials are known. This project aims to explore and characterize a new family of proposed magnetic Weyl semimetals through single crystal growth and magneto-electrical transport measurements. It will unlock the key ingredients necessary for discovery and design of new magnetic Weyl semimetals. The project includes a comprehensive outreach strategy and provides important training in material synthesis and characterization for high-school, undergraduate, and graduate students.Technical Abstract: Magnetic Weyl semimetals, characterized by broken spatial inversion and time-reversal symmetries whose quasiparticle excitations are Weyl fermions, have recently attracted much attention because they show a variety of new topological states that are promising for diverse technological applications, including quantum bits. Despite significant theoretical and experimental work, only a few such materials are known. The objective of this project is to discover and design such materials through the investigation of families of magnetic strongly correlated intermetallic compounds via single crystal growth and measurement of magnetotransport properties (i.e., the Hall effect). Together with theoretical calculations and angle-resolved photo-emission spectroscopy (ARPES) measurements, this project will provide deeper insight into how Weyl fermions manifest in condensed matter systems, broaden the current research field by discovering many new magnetic Weyl semimetal families, and study the interplay between Weyl fermions, electron-electron correlations and quantum criticality.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.