Titanium-vanadium dioxide or Ti_xV_1−xO₂ films for 0 ≤ x ≤ 1 were examined using ellipsometry, and their optical constants (n and k) at visible and near-infrared wavelengths were determined at temperatures (T) below, at, and above the semiconductive-to-metallic phase transition (SMT) temperature (T_SM). Ellipsometric analysis was performed for each x at each T using a wavelength dispersion model, i.e., a combination of Lorentz oscillators and a Drude free electron model. The ellipsometric analyses provided information on the electronic band transition caused by the SMT and the influence of cationic replacement (Ti↔V) on the SMT. The results revealed that when x ≤ 0.05, close to the SMT, the energy gap of the interband transition O_2p→V_3d varied from ≈3.5 eV to ≈3.1 eV, and the quantity of electrons in the interband transition decreased by half. In addition, the energy gap monotonically increased to 4.2 eV when x was increased to 1. Moreover, the energy gap of the split V_3d intraband transition varied from ≈1.4 eV to zero, and the quantity of electrons in the intraband transition increased by a factor of four. Furthermore, when x ≥ 0.2, close to the SMT, the energy gap of the intraband transition varied from ≈1.4 eV to a constant positive value, with the generation of a small number of conductive electrons, depending on x.

中文翻译：

---

半导体-金属相变过程中0≤x≤1的钛钒二氧化物（TixV1-xO2）薄膜电子行为的椭圆仪研究

钛-钒氧化物或Ti _X V _{1- X} ø ₂膜为0≤ X  ≤1使用椭圆光度法进行了检查，以及它们的光学常数（Ñ和ķ在温度（测定在可见光和近红外波长）Ť下文），在和以上所述半导电到金属的相变（SMT）温度（Ť _SM）。在每个T处对每个x进行椭偏分析使用波长色散模型，即洛伦兹振荡器和德鲁德自由电子模型的组合。椭偏分析提供了有关SMT引起的电子能带跃迁以及阳离子替代（Ti↔V）对SMT的影响的信息。结果表明，当X  ≤0.05，接近SMT中，带间跃迁的O的能隙_{2 p} →V _{3 d}从≈3.5电子伏特变化到≈3.1电子伏特，且电子在带间跃迁的数量减少了一半。另外，当x增加到1时，能隙单调增加到4.2 eV 。此外，分裂V _{3 d}的能隙带内跃迁的范围从≈1.4eV到零，并且带内跃迁中的电子数量增加了四倍。此外，当X  ≥0.2，接近SMT中，带内跃迁从≈1.4电子伏特变化到恒定正值，用少量导电电子，这取决于产生的能隙X。