Antiferromagnetism, superconductivity, and pseudogap in three-layered high-T-c cuprates Ba2Ca2Cu3O6(F,O)(2) probed by Cu-NMR

作者：Shimizu Sunao^*; Tabata Shin ichiro; Mukuda Hidekazu; Kitaoka Yoshio; Shirage Parasharam M; Kito Hijiri; Iyo Akira

来源：Physical Review B, 2011, 83(21): 214514.

DOI：10.1103/PhysRevB.83.214514

We report on the phase diagram of antiferromagnetism (AFM) and superconductivity (SC) in three-layered Ba2Ca2Cu3O6(F,O)(2) by means of Cu-NMR measurements. It is demonstrated that AFM and SC coexist uniformly in three-layered compounds as well as in four- and five-layered ones. The critical hole density pc for the long-range AFM order is determined as p(c) similar or equal to 0.075, which is larger than p(c) similar or equal to 0.02 and 0.055 in single- and bilayered compounds, and smaller than p(c) similar or equal to 0.08-0.09 and 0.10-0.11 in four- and five-layered compounds, respectively. This variation of p(c) is attributed to the magnetic interlayer coupling, which becomes stronger as the stacking number of CuO2 layers increases; that is, the uniform coexistence of AFM and SC is a universal phenomenon in underdoped regions when a magnetic interlayer coupling is strong enough to stabilize an AFM ordering. In addition, we highlight an unusual pseudogap behavior in three-layered compounds-the gap behavior in low-energy magnetic excitations collapses in an underdoped region where the ground state is the AFM-SC mixed phase.

• 出版日期2011-6-10