Localization phenomena in disordered tantalum films

0476820 - FZÚ 2018 RIV CH eng J - Článek v odborném periodiku
Kovaleva, Natalia - Chvostová, Dagmar - Dejneka, Alexandr
Localization phenomena in disordered tantalum films.
Metals. Roč. 7, č. 7 (2017), 1-12, č. článku 257. E-ISSN 2075-4701
Grant CEP: GA ČR GA15-13778S
Institucionální podpora: RVO:68378271
Klíčová slova: disordered metals * weak and Anderson localization * dc transport * spectroscopic ellipsometry
Obor OECD: Condensed matter physics (including formerly solid state physics, supercond.)
Impakt faktor: 1.704, rok: 2017

Using dc transport and wide-band spectroscopic ellipsometry techniques we study localization phenomena in highly disordered metallic β-Ta films grown by rf sputtering deposition. The dc transport study implies non-metallic behavior (dρ/dT < 0), with negative temperature coefficient of resistivity (TCR). We found that as the absolute TCR value increased, specifying an elevated degree of disorder, the free charge carrier Drude response decreases, indicating the enhanced charge carrier localization. Moreover, we found that the pronounced changes occur at the extended spectral range, involving not only the Drude resonance, but also the higher-energy Lorentz bands, in evidence of the attendant electronic correlations. We propose that the charge carrier localization, or delocalization, is accompanied by the pronounced electronic band structure reconstruction due to many-body effects, which may be the key feature for understanding the physics of highly disordered metals.
Trvalý link: http://hdl.handle.net/11104/0273235