论文标题
通过修饰氧气化学计量法来控制氧化钒薄膜中的金属胰蛋白晶体过渡
Controlling Metal-Insulator Transitions in Vanadium Oxide Thin Films by Modifying Oxygen Stoichiometry
论文作者
论文摘要
Vanadium oxides are strongly correlated materials which display metal-insulator transitions as well as various structural and magnetic properties that depend heavily on oxygen stoichiometry.因此，这对于精确控制这些材料中的氧气化学计量至关重要，尤其是在薄膜中。 This work demonstrates a high-vacuum gas evolution technique which allows for the modification of oxygen concentration in VOX thin films by carefully tuning thermodynamic conditions. We were able to control the evolution between VO2, V3O5, and V2O3 phases on sapphire substrates, overcoming the narrow phase stability of adjacent Magnéli phases.发现各种退火途径可以达到所需的相位，并最终控制金属 - 绝缘体过渡（MIT）。 The pronounced MIT of the transformed films along with the detailed structural investigations based on x-ray diffraction measurements and reciprocal space mapping show that optimal stoichiometry is obtained and stabilized.使用此技术，我们发现薄膜V-O相图与由于应变和有限尺寸效应而导致的散装材料的相图不同。 Our study demonstrates new pathways to strategically tune the oxygen stoichiometry in complex oxides and provides a roadmap for understanding the phase stability of VOX thin films.
Vanadium oxides are strongly correlated materials which display metal-insulator transitions as well as various structural and magnetic properties that depend heavily on oxygen stoichiometry. Therefore, it is crucial to precisely control oxygen stoichiometry in these materials, especially in thin films. This work demonstrates a high-vacuum gas evolution technique which allows for the modification of oxygen concentration in VOX thin films by carefully tuning thermodynamic conditions. We were able to control the evolution between VO2, V3O5, and V2O3 phases on sapphire substrates, overcoming the narrow phase stability of adjacent Magnéli phases. A variety of annealing routes were found to achieve the desired phases and eventually to control the metal-insulator transition (MIT). The pronounced MIT of the transformed films along with the detailed structural investigations based on x-ray diffraction measurements and reciprocal space mapping show that optimal stoichiometry is obtained and stabilized. Using this technique, we find that the thin film V-O phase diagram differs from that of the bulk material due to strain and finite size effects. Our study demonstrates new pathways to strategically tune the oxygen stoichiometry in complex oxides and provides a roadmap for understanding the phase stability of VOX thin films.
