NEB: Novel Quantum Switches Using Heterogeneous Atomically Layered Nanostructures

该项目被授予2020年及以后的纳米电子学奖，由国家科学基金会的多个董事和部门以及半导体研究公司的纳米电子学研究计划提供支持。技术：对在低功耗下运行的高性能电子开关的研究产生了许多超出传统半导体器件结构中的电荷流控制的概念。这些新颖的器件基于可选状态变量的使用，包括单粒子量子系统的特性，如自旋、伪自旋和载流子函数相位，以及关联多体量子系统的特性，如激子和激子凝聚体。这个项目的目标是开发变革性技术的基础，这种技术将通过使用这种量子状态变量的高性能电子设备的可用性而成为可能，而不是传统的半经典电荷传输。为此，哥伦比亚大学和佛罗里达大学的一个研究小组致力于这种量子开关的制造、表征和理论分析。这项研究利用了最近在合成原子薄层范德华固体和由这种层状材料组合形成的异质结构方面的技术进步。石墨烯和六方氮化硼原子薄层的异质结所表现出的优异的电学特性证明了这种方法的潜力。在这个项目中，设备是由这样发展良好的材料系统制造的，其中主要的制造挑战涉及对几何形状和界面清洁度的精确控制。该项目的主要研究内容如下：(I)基于van der Waals材料共层压、原子层沉积工艺和先进的图案化技术的原子薄异质结器件的组装和制造；(Ii)通过电学和光学测量分析弱耦合层状异质结器件结构中独特的量子相干输运过程；(Iii)基于量子相干建立新的状态变量；以及(Iv)基于新的状态变量的开关器件的演示、表征和理论建模。这项研究工作产生的器件在开关速度和能量消耗方面的性能大大超过了传统半导体器件技术的限制。非技术：基于低维功能材料平台的新型电子器件的开发开启了基础和应用研究的重要方向。实用的高性能、低能耗开关器件的可获得性对于电子和相关信息技术产业的持续发展具有重要意义。因此，基于新开关原理的设备演示具有广泛的技术影响。该团队的不同能力也大大增加了哥伦比亚大学和合作机构的学生和博士后的教育机会。该项目进行的高度跨学科研究为研究生和博士后以及本科生提供了尖端培训。该团队通过提供新的讲座和实验室课程，以及修改现有课程，将研究活动与教育工作相结合。该团队还通过赞助高中生暑期研究项目，开展更广泛的教育推广活动。通过培训积极性很高的高中生，以及加强与当地K-12教育工作者的互动，向学生介绍一线研究，为K-12推广做出了重大努力。

This project is awarded under the Nanoelectronics for 2020 and Beyond competition, with support by multiple Directorates and Divisions at the National Science Foundation as well as by the Nanoelectronics Research Initiative of the Semiconductor Research Corporation.TECHNICAL: The search for high-performance electronic switches operating at low power dissipation has generated many concepts that go beyond the control of charge flow in traditional semiconductor device structures. These novel devices are based on the use of alternative state variables, including the characteristics of single-particle quantum systems, such as spin, pseudospin, and carrier wave-function phase, and the characteristics of correlated many-body quantum systems, such as excitons and exciton condensates. The goal of this project is to develop the basis for transformative technology that would be made possible by the availability of high-performance electronic devices employing such quantum state variables, rather than traditional semi-classical transport of charge. To this end, a team of investigators at Columbia University and University of Florida is devoted to the fabrication, characterization, and theoretical analysis of such quantum switches. The research exploits recent technological advances in the synthesis of atomically thin layers of van der Waals solids and heterostructures formed from combinations of such layered materials. The potential of this approach is exemplified by the excellent electrical characteristics exhibited by heterostructures of atomically thin layers of graphene and hexagonal boron nitride. In this project, devices are built from such well-developed material systems, where the primary fabrication challenges involve precise control over geometry and interface cleanliness. The key research components of the project are as follows: (i) The assembly and fabrication of atomically thin heterostructure devices based on the co-lamination of van der Waals materials, atomic-layer deposition processes, and advanced patterning techniques; (ii) the analysis of distinctive quantum coherent transport processes in weakly coupled layered heterojunction device structures by electrical and optical measurements; (iii) the establishment of new state variables based on quantum coherence; and (iv) the demonstration, characterization, and theoretical modeling of switching devices based on novel state variables. Devices resulting from this research effort promise performance with respect to switching speed and energy dissipation that significantly exceeds the limits imposed by conventional semiconductor device technology.NON-TECHNICAL: The development of the new electronic devices based on low-dimensional functional material platforms opens important directions in both fundamental and applied research. The availability of practical high-performance, low-energy switching devices is of great significance for the continued advancement of electronics and the associated information technology industry. Thus, the demonstration of devices based on new switching principles has the potential for broad technological impact. The diverse capabilities of the team also significantly enhance the educational opportunities for students and postdocs at Columbia and at collaborating institutions. The highly interdisciplinary research carried out in this project provides cutting-edge training for graduate students and postdocs, as well as for undergraduate students. The team integrates research activities with educational efforts by offering new lecture and laboratory courses, as well as modifying existing ones. The team also undertakes broader educational outreach through sponsorship of summer research projects for high school students. Significant efforts are made toward K-12 outreach by training of highly motivated high school students, and by enhancing interactions with local K-12 educators to introduce front-line research to students.