Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208, USA.
Nano Lett. 2009 Dec;9(12):4527-32. doi: 10.1021/nl9028973.
The electrical resistance of single VO(2) nanobeams was measured while simultaneously mapping the domain structure with Raman spectroscopy to investigate the relationship between structural domain formation and the metal-insulator transition. With increasing temperature, the nanobeams transformed from the insulating monoclinic M(1) phase to a mixture of the Mott-insulating M(2) and metallic rutile phases. Domain fractions were used to extract the temperature dependent resistivity of the M(2) phase, which showed an activated behavior consistent with the expected Mott-Hubbard gap. Metallic monoclinic phases were also produced by direct injection of charge into devices, decoupling the Mott metal-insulator transition from the monoclinic to rutile structural phase transition.
单 VO(2) 纳米梁的电阻在同时用拉曼光谱绘制其域结构的情况下进行了测量，以研究结构域形成与金属-绝缘体转变之间的关系。随着温度的升高，纳米梁从绝缘的单斜 M(1) 相转变为 Mott 绝缘 M(2) 相和金属金红石相的混合物。域分数用于提取 M(2) 相的温度相关电阻率，其表现出与预期的 Mott-Hubbard 能隙一致的激活行为。通过直接向器件注入电荷也产生了金属单斜相，从而将莫特金属-绝缘体转变与单斜相向金红石结构相变解耦。
