2024-03-29T11:16:42Zhttps://eprints.lib.hokudai.ac.jp/dspace-oai/requestoai:eprints.lib.hokudai.ac.jp:2115/579662022-11-17T02:08:08Zhdl_2115_20057hdl_2115_148Thermopower analysis of the electronic structure around the metal-insulator transition in V1-xWxO2Katase, TakayoshiEndo, KenjiOhta, Hiromichi549The electronic structure across the metal-insulator (MI) transition of electron-doped V1-xWxO2 epitaxial films (x = 0-0.06) grown on alpha-Al2O3 substrates was studied by means of thermopower (S) measurements. Significant increase of vertical bar S vertical bar values accompanied by MI transition was observed, and the transition temperatures of S (T-S) decreased with x in a good linear relation with MI transition temperatures. vertical bar S vertical bar values of V1-xWxO2 films at T > T-S were constant at low values of 23 mu VK-1 independently of x, which reflects a metallic electronic structure, whereas those at T < T-S almost linearly decreased with logarithmic W concentrations. The gradient of -213 mu VK-1 agrees well with -k(B)/e ln10 (-198 mu VK-1), suggesting that V1-xWxO2 films have insulating electronic structures with a parabolic density of state around the conduction band bottom.American Physical SocietyJournal Articleapplication/pdfhttp://hdl.handle.net/2115/57966https://eprints.lib.hokudai.ac.jp/dspace/bitstream/2115/57966/1/PhysRevB.90.161105.pdf1098-01211550-235XAA11187113Physical review. B9016161105-1161105-42014-10-21enginfo:doi/10.1103/PhysRevB.90.161105©2014 American Physical Societypublisher