Collaborative Proposal: Harvesting electronic flat bands and strong spin-orbit coupling for novel functionalities in metal monochalcogenides

合作提案：收获电子平带和强自旋轨道耦合以实现金属单硫属化物的新功能

• 批准号: 2219048
• 负责人: Chun Ning Lau
• 金额: $ 29.74万
• 依托单位: Ohio State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2025-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2219048&HistoricalAwards=false
• 关键词: Collaborative; Proposal; Harvesting; electronic; flat

NON-TECHNICAL DESCRIPTIONMaterials made from a single atomic layer or a few layers have electronic properties that profoundly differ from those of bulk materials. For example, two-dimensional materials can combine high mechanical strength and optical transparency with efficient charge transport. These properties could be exploited to create new classes of devices with novel functionalities. One could make a material that could become electrically conducting or insulating, but also magnetic or non-magnetic, at the flip of a switch. Such a material could enable development of ultra-sensitive optical or magnetic sensors. This research project will focus on one class of ultrathin materials—metal monochalcogenides such as gallium selenide or gallium sulfide. Researchers will investigate these materials and seek to endow them with specific electrical, magnetic, and optical properties upon exfoliation, encapsulation and twisting. This research will be integrated with the mentoring and training of the next generation of physicists, materials scientists, and engineers. Both team members actively recruit and mentor undergraduate and graduate students from underrepresented groups, while also reaching out to high school teachers and students. The team collaborates with the National High Magnetic Field Laboratory at Florida State University to develop hands-on instructional materials for schools in the surrounding North Florida counties.TECHNICAL DESCRIPTIONThe goal of this collaborative project is to harness the electronic flat bands and strong spin-orbit coupling (SOC) inherent to the family of the III-VI metal monochalcogenides (MMCs), to achieve gate-tunable ferromagnetism and half-metallicity, fractional quantum Hall (QH) states in the limit of large SOC. The work will enable novel spintronic, valleytronic and optoelectronic devices. Investigators will: i) explore, tune, and understand the nature of the fractional quantum Hall states in the regime of large SOC, which has implications for topological quantum computation; ii) achieve gate-tunable ferromagnetism due to half-metallicity and their interplay with other possible correlated states (such as possible superconductivity and correlated phases ) in hole-doped few-layer MMCs; iii) create spin- and valley-polarized currents in heterostructures based on metal monochalcogenides on transition metal dichalcogenides, and iv) achieve gate-tunable excitonics in MMCheterostructures with moiré superlattices, for optoelectronics with an unprecedented level of tunability. This project will directly support one graduate student at each participating institutions. The students will circulate among both institutions and other national facilities. In addition, both principal investigators will continue their established efforts at mentoring undergraduate and high school students, while also recruiting and mentoring students from underrepresented groups.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.

非技术描述由单原子层或几层制成的材料具有与块状材料截然不同的电子特性，例如，二维材料可以将高机械强度和光学透明度与有效的电荷传输结合起来。人们可以利用这种材料来创造具有新颖功能的新型设备，这种材料可以在按下开关时变得导电或绝缘，也可以具有磁性或非磁性。该研究项目将重点研究一类超薄材料——金属单硫族化物，例如硒化镓或硫化镓，研究人员将研究这些材料，并寻求赋予它们特定的电、磁和光学特性。这项研究将与下一代物理学家、材料科学家和工程师的指导和培训相结合，两个团队成员都积极招募和指导本科生和研究生。该团队与佛罗里达州立大学国家高磁场实验室合作，为北佛罗里达州周边县的学校开发实践教学材料。技术描述本次合作的目标。该项目的目的是利用 III-VI 族金属单硫属化物 (MMC) 家族固有的电子平带和强自旋轨道耦合 (SOC)，以实现栅极可调铁磁性和大型 SOC 极限下的半金属性、分数量子霍尔 (QH) 态这项工作将使新型自旋电子、谷电子和光电器件成为可能： i) 探索、调整和理解分数量子霍尔态的性质。大型 SOC 的状态，这对拓扑量子计算具有影响；ii) 由于半金属性及其与其他可能的相关状态（例如可能的状态）的相互作用，实现门可调谐铁磁性；超导和相关相）在空穴掺杂的几层MMC中；iii）在基于过渡金属二硫属化物的金属单硫属化物的异质结构中产生自旋和谷极化电流，以及iv）在具有莫尔超晶格的MMC异质结构中实现栅极可调激子，该项目将直接支持每个参与机构的一名研究生。此外，两位主要研究人员将继续其指导本科生和高中生的既定努力，同时招募和指导来自代表性不足群体的学生。该奖项反映了 NSF 的法定使命，并被视为值得通过使用基金会的智力优点和更广泛的影响审查标准进行评估来支持。

项目成果

Quantum Hall effect in a two-dimensional semiconductor with large spin-orbit coupling

具有大自旋轨道耦合的二维半导体中的量子霍尔效应

• DOI: 10.1103/physrevb.106.045307
• 发表时间: 2022
• 期刊: Physical Review B
• 影响因子: 3.7
• 作者: Shcherbakov, D.;Yang, Jiawei;Memaran, Shahriar;Watanabe, Kenji;Taniguchi, Takashi;Smirnov, Dmitry;Balicas, Luis;Lau, Chun Ning
• 通讯作者: Lau, Chun Ning