Uniform mixing of high-TcTc superconductivity and antiferromagnetism in HgBa2Ca4Cu5O12+δHgBa2Ca4Cu5O12+δ

We report a Cu-NMR study on under-doped Hg-based five-layered cuprate HgBa2Ca4Cu5O12+δHgBa2Ca4Cu5O12+δ (Hg-1245(UD)) with a Tc=72K. The antiferromagnetism (AFM) has been found to take place at TN=290K, exhibiting a large antiferromagnetic moment MAF(IP)MAF(IP) of 0.67–0.69μB0.67–0.69μB at three inner planes (IPs) that is comparable to the values reported for non-doped cuprates. It suggests that the IP may be in a non-doped regime. The AFM with MAF(OP)∼0.1μBMAF(OP)∼0.1μB is also detected even at two outer planes (OPs) that are responsible for the onset of superconductivity (SC). The high-TcTc SC at Tc=72K can uniformly coexist on a microscopic level with the AFM at OP layers. This is the first microscopic evidence for the uniform mixed phase of AFM and SC on a single CuO2CuO2 plane in a simple environment without any vortex lattice and/or stripe order.