Tunable polaronic conduction in anatase TiO2.
نویسندگان
چکیده
Oxygen vacancies created in anatase TiO(2) by UV photons (80-130 eV) provide an effective electron-doping mechanism and induce a hitherto unobserved dispersive metallic state. Angle resolved photoemission reveals that the quasiparticles are large polarons. These results indicate that anatase can be tuned from an insulator to a polaron gas to a weakly correlated metal as a function of doping and clarify the nature of conductivity in this material.
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ورودعنوان ژورنال:
- Physical review letters
دوره 110 19 شماره
صفحات -
تاریخ انتشار 2013