论文信息 - The metal-non-metal transition in VO2: X-ray photoemission and resistivity measurements

The metal-non-metal transition in VO2: X-ray photoemission and resistivity measurements

The semiconductor-metal transition in VO2 has been investigated by means of XPS measurements. The band gap in the semiconducting region is found to be temperature-dependent with a room temperature value of Eg=0.3 eV, in agreement with resistivity measurements. The core lines, which are asymmetric below Tnu broaden and become symmetric above Tt. A model is discussed to explain the broadening in the metallic region, which requires that the core hole-valence electron interaction is comparable to the bandwidth. The relative shift of the O 1s and V 2p peak positions below and above Tt indicates that the charges on the ions are highest in the metallic phase, suggesting a more ionic bond in this region.

[1] John B. Goodenough,et al. The two components of the crystallographic transition in VO2 , 1971 .

[2] Sebastian Doniach,et al. Many-electron singularity in X-ray photoemission and X-ray line spectra from metals , 1970 .

[3] C. Blaauw,et al. METAL-NONMETAL TRANSITION IN VO2 - FE-57 MOSSBAUER STUDY , 1974 .

[4] G. Rao,et al. Phase transitions and conductivity anomalies in solid solutions of VO2 with TiO2, NbO2, and MoO2 , 1971 .

[5] G. Hyland. On the electronic phase transitions in the lower oxides of vanadium , 1968 .

[6] D. Adler,et al. Semiconductor-To-Metal Transitions in Transition-Metal Compounds , 1967 .

[7] Mats Nygren,et al. Electrical and magnetic properties of V1−xWxO2, 0 ≤ x ≤ 0.060 , 1972 .

[8] C. J. Hearn. Phonon softening and the metal-insulator transition in VO2 , 1972 .

[9] F. J. Morin,et al. Oxides Which Show a Metal-to-Insulator Transition at the Neel Temperature , 1959 .

[10] William Paul,et al. Hall effect in VO$sub 2$ near the semiconductor-to-metal transition , 1973 .

[11] T. Mitsuishi. On the Phase Transformation of VO2 , 1967 .

[12] C. Dominicis,et al. Singularities in the X-Ray Absorption and Emission of Metals. III. One-Body Theory Exact Solution , 1969 .