title: Normal-state charge dynamics in doped BaFe₂As₂: roles of doping and necessary ingredients for superconductivity.
abstract: In high-transition-temperature superconducting cuprates and iron arsenides, chemical doping plays an important role in inducing superconductivity. Whereas in the cuprate case, the dominant role of doping is to inject charge carriers, the role for the iron arsenides is complex owing to carrier multiplicity and the diversity of doping. Here, we present a comparative study of the in-plane resistivity and the optical spectrum of doped BaFe₂As₂, which allows for separation of coherent (itinerant) and incoherent (highly dissipative) charge dynamics. The coherence of the system is controlled by doping, and the doping evolution of the charge dynamics exhibits a distinct difference between electron and hole doping. It is found in common with any type of doping that superconductivity with high transition temperature emerges when the normal-state charge dynamics maintains incoherence and when the resistivity associated with the coherent channel exhibits dominant temperature-linear dependence.
authors: 1] Department of Physics, University of Tokyo, Tokyo 113-0033, Japan [2] National Institute of Advanced Industrial Science and Technology, Tsukuba 305-8568, Japan [3] JST, Transformative Research-Project on Iron Pnictides (TRIP), Tokyo 102-0075, Japan [4].
authors: M
authors: M
authors: Nakajima
authors: 1] Department of Physics, University of Tokyo, Tokyo 113-0033, Japan [2] National Institute of Advanced Industrial Science and Technology, Tsukuba 305-8568, Japan [3] JST, Transformative Research-Project on Iron Pnictides (TRIP), Tokyo 102-0075, Japan.
authors: S
authors: S
authors: Ishida
authors: 1] Department of Physics, University of Tokyo, Tokyo 113-0033, Japan [2] JST, Transformative Research-Project on Iron Pnictides (TRIP), Tokyo 102-0075, Japan.
authors: T
authors: T
authors: Tanaka
authors: 1] National Institute of Advanced Industrial Science and Technology, Tsukuba 305-8568, Japan [2] JST, Transformative Research-Project on Iron Pnictides (TRIP), Tokyo 102-0075, Japan.
authors: K
authors: K
authors: Kihou
authors: 1] National Institute of Advanced Industrial Science and Technology, Tsukuba 305-8568, Japan [2] JST, Transformative Research-Project on Iron Pnictides (TRIP), Tokyo 102-0075, Japan.
authors: Y
authors: Y
authors: Tomioka
authors: Department of Physics, Chiba University, Chiba 263-8522, Japan.
authors: T
authors: T
authors: Saito
authors: 1] National Institute of Advanced Industrial Science and Technology, Tsukuba 305-8568, Japan [2] JST, Transformative Research-Project on Iron Pnictides (TRIP), Tokyo 102-0075, Japan.
authors: C H
authors: CH
authors: Lee
authors: 1] JST, Transformative Research-Project on Iron Pnictides (TRIP), Tokyo 102-0075, Japan [2] Department of Physics, Chiba University, Chiba 263-8522, Japan.
authors: H
authors: H
authors: Fukazawa
authors: 1] JST, Transformative Research-Project on Iron Pnictides (TRIP), Tokyo 102-0075, Japan [2] Department of Physics, Chiba University, Chiba 263-8522, Japan.
authors: Y
authors: Y
authors: Kohori
authors: 1] Department of Physics, University of Tokyo, Tokyo 113-0033, Japan [2] JST, Transformative Research-Project on Iron Pnictides (TRIP), Tokyo 102-0075, Japan.
authors: T
authors: T
authors: Kakeshita
authors: 1] National Institute of Advanced Industrial Science and Technology, Tsukuba 305-8568, Japan [2] JST, Transformative Research-Project on Iron Pnictides (TRIP), Tokyo 102-0075, Japan.
authors: A
authors: A
authors: Iyo
authors: 1] National Institute of Advanced Industrial Science and Technology, Tsukuba 305-8568, Japan [2] JST, Transformative Research-Project on Iron Pnictides (TRIP), Tokyo 102-0075, Japan.
authors: T
authors: T
authors: Ito
authors: 1] National Institute of Advanced Industrial Science and Technology, Tsukuba 305-8568, Japan [2] JST, Transformative Research-Project on Iron Pnictides (TRIP), Tokyo 102-0075, Japan.
authors: H
authors: H
authors: Eisaki
authors: 1] Department of Physics, University of Tokyo, Tokyo 113-0033, Japan [2] JST, Transformative Research-Project on Iron Pnictides (TRIP), Tokyo 102-0075, Japan.
authors: S
authors: S
authors: Uchida