Rowland Institute at Harvard, Cambridge Massachusetts 02142, USA.
Opt Lett. 2011 May 15;36(10):1927-9. doi: 10.1364/OL.36.001927.
We present results on terahertz (THz) spectroscopy on epitaxial vanadium dioxide (VO(2)) films grown on sapphire across the metal-insulator transition. X-ray diffraction indicates the VO(2) film is highly oriented with the crystallographic relationship: (002)(film)//(0006)(sub) and 010//2 ̅1 ̅10. THz studies measuring the change in transmission as a function of temperature demonstrate an 85% reduction in transmission as the thin film completes its phase transition to the conducting phase, which is much greater than the previous observation on polycrystalline films. This indicates the crucial role of microstructure and phase homogeneity in influencing THz properties.
我们展示了在蓝宝石上外延生长的氧化钒（VO(2)）薄膜在金属-绝缘体相变过程中的太赫兹（THz）光谱学研究结果。X 射线衍射表明，VO(2)薄膜具有高度取向性，晶体学关系为（002）（薄膜）//（0006）（衬底）和[010]（薄膜）//[2 ̅1 ̅10]（衬底）。THz 研究测量了透射率随温度的变化，结果表明，当薄膜完全转变为导电相时，透射率降低了 85%，这比以前在多晶薄膜上的观察结果大得多。这表明微结构和相均匀性在影响 THz 性质方面起着至关重要的作用。
