报告题目: |
Metal-Insulator Transition of VO2: Potential in Transistors and Actuators |
报告人: |
刘锴博士 |
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UCBerkeley
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报告时间: |
2013-04-10 15:00 |
报告地点: |
纳米中心四楼报告厅 |
主办单位: |
物理系 |
简介: |
Vanadium dioxide (VO2) undergoes a metal-insulator phase transition (MIT) accompanied by a structural transition of lattice. Whether the MIT is fundamentally driven by Mott transition (electron–electron correlation) or Peierls transition (electron–lattice interaction) has been debated for decades. A threshold free electron density exists in the transition from the insulator to metal phase, implying that the MIT can be triggered by electrostatic carrier accumulation. VO2 also shrinks by a transformation strain of ~ 1% along the c axis of the metal phase (cR) across the MIT, and meanwhile outputs a huge mechanical work density.
In this talk, I will present our work on controlling and utilizing both of the electronic phase transition and the structural phase transition of VO2. A reversible control of the conductance of VO2 is realized by electrostatic gating with an electrolyte or ionic liquid as medium. And VO2-based bimorphs are fabricated as powerful linear and torsional actuators which demonstrate superior performance, high durability, diversity in responsive stimuli, and versatile working environments. These efforts make VO2 a promising material in transistors and micro actuators. |
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