Electrically Controlled Metal-Insulator Transition and Its Terahertz Applications

概述：我们提出了研究基于二氧化钒的可逆金属-绝缘体转变（MIT）的新型功能器件的电子和光子性质的巨大变化。VO_2的电阻率变化4 ~ 5个数量级，折射率变化超过15%，相对于自由空间折射率对比度大于30。这种独特的特性组合激发了对生物素酶转换机制的研究、对其特性的控制以及太赫兹（THz）功能组件的开发。我们将探索VO 2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电驱动时，并开发新的功能器件用于THz开关和调制应用，其目的是可重构操作。通过对相变机理和影响相变的因素的研究，速度？we will engineer工程the materialstructure材料structure结构to achieve实现abrupt突然？数码的？开关和可控双折射相变？模拟？调变研究结果将为电控金属-绝缘体相变提供基础性的认识，促进相变材料在电子和光子学领域的应用。更广泛的影响：相变研究将为创新功能器件的开发提供新的机遇。这些设备将展示前所未有的电子和光子应用的操作原理，除了基本的科学理解。所提出的器件将在太赫兹技术中得到广泛的应用，该项目为跨学科的研究、教育和培训提供了极好的机会.外联工作将吸引新生，特别是来自代表性不足群体的新生，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.