Non-Fermi-liquid to Fermi-liquid transports in iron-pnictide Ba(Fe1-xCox)(2)As-2 and the electronic correlation strength in superconductors newly probed by the normal-state Hall angle

作者：Wang L M^*; Wang Chih Yi; Zen Sha Min; Chang Jin Yuan; Kuo C N; Lue C S; Chang L J; Su Y; Wolf Th; Adelmann P

来源：New Journal of Physics, 2017, 19(3): 033039.

DOI：10.1088/1367-2630/aa649e

• iron-based superconductor
• electronic correlation
• non-Fermi-liquid
• Hall angle

Electrical transports in iron-pnictide Ba(Fe1-xCox)(2)As-2 (BFCA) single crystals are heavily debated in terms of the hidden Fermi-liquid (HFL) and holographic theories. Both HFL and holographic theories provide consistent physic pictures and propose a universal expression of resistivity to describe the crossover of transports from the non-Fermi-liquid (FL) to FL behavior in these so-called 'strange metal' systems. The deduced spin exchange energy J and model-dependent energy scale Win BFCA are almost the same, or are of the same order of several hundred Kelvin for over-doped BFCA, which is in agreement with the HFL theory. Moreover, a drawn line of W/3.5 for BFCA in the higher-doping region up to the right demonstrates the crossover from non-FL-like behavior to FL-like behavior at high doping, and shows a new phase diagram of BFCA. The electronic correlation strength in superconductors has been newly probed by the normal-state Hall angle, which found that, for the first time, correlation strength can be characterized by the ratios of T-c to the Fermi temperature T-F, J/T-F, and the transverse mass to longitudinal mass.

• 出版日期2017-3-28