Electrically Controlled Metal-Insulator Transition and Its Terahertz Applications

概述：我们提出研究基于二氧化钒的可逆金属-绝缘体转变（MIT）的新功能器件的电子和光子特性的巨大变化。VO2的电阻率变化4 ~ 5个数量级。折射率的变化超过15%，相对于自由空间的折射率反差大于3。这种独特的性质组合激发了对其相变机制的研究，对其性质的控制，以及对太赫兹（THz）功能组件的开发。知识优势：我们将探索VO2相变的基本物理，特别是在脉冲电流模式或栅极电场模式下的电驱动，并开发用于太赫兹开关和调制应用的新功能器件，目的是可重构操作。通过对相变机理和影响相变速度的因素的研究。我们将设计材料结构以实现突然的数字化。模拟流体的开关和可控渗透相变调制。该结果将为电控金属-绝缘体转变提供基本的认识，并促进相变基材料在电子和光子领域的应用。更广泛的影响：相变研究将为实现创新功能器件提供新的机会。这些设备将展示前所未有的电子和光子应用的操作原理，以及基本的科学理解。所提出的元件将在太赫兹技术中得到广泛应用。该项目为跨学科研究、教育和培训提供了极好的机会。拓展工作将吸引新的学生，特别是那些来自代表性不足的群体的学生，进入科学和工程领域。

Overview: We propose to investigate dramatic changes in electronic and photonicproperties of new functional devices based on the reversible metal-insulator transition(MIT) of vanadium dioxide. The electrical resistivity of VO2 changes by 4 to 5 orders.Variations in refractive index exceed 15%, giving an index contrast of greater than 3relative to free space. This unique combination of properties motivates the study of itsphase transition mechanisms, control of its properties, and development of terahertz(THz) functional components.Intellectual Merit: We will explore the fundamental physics of VO2 phase transition,particularly when driven electrically in pulsed current mode or in gate electric-field mode,and develop new functional devices for THz switching and modulation applications withthe aim of reconfigurable manipulation. Through the study of phase transitionmechanisms and factors to influence the transition ?speed? we will engineer the materialstructure to achieve abrupt ?digital? switching and controllable percolative phasetransition for ?analog? modulation. The result will provide fundamental understanding ofelectrically controlled metal-insulator transition and promote the application of phasetransition-based materials for electronic and photonic applications.Broader Impact: Study of phase transitions will provide new opportunities to achieveinnovative functional devices. These devices will exhibit unprecedented operationalprinciples for electronic and photonic applications, in addition to fundamental scientificunderstanding. The proposed components will find broad applications in THz technology.The project provides excellent opportunities for interdisciplinary research education andtraining. Outreach efforts will attract new students, especially those fromunderrepresented groups, to science and engineering fields.