Physics and Astronomy, Ames Laboratory
Journal or Book Title
Physical Review B
We demonstrate that the thermopower (S) can be used to probe the spin fluctuations (SFs) in proximity to the quantum critical point (QCP) in Fe-based superconductors. The sensitivity of S to the entropy of charge carriers allows us to observe an increase of S/T in Ba(Fe1−xCox)2As2 close to the spin-density-wave (SDW) QCP. This behavior is due to the coupling of low-energy conduction electrons to two-dimensional SFs, similar to heavy-fermion systems. The low-temperature enhancement of S/T in the Co substitution range 0.02
American Physical Society
Arsenijevic, S.; Hodovanets, H.; Gaal, R.; Forro, L.; Bud’ko, Sergey L.; and Canfield, Paul C., "Signatures of quantum criticality in the thermopower of Ba(Fe1-xCox)(2)As-2" (2013). Physics and Astronomy Publications. 605.