2018/05/01 by H. Murayama, Y. Sato, R. Kurihara +12 · 59 citations
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Anisotropy #Chemical and Physical Properties of Materials #Cuprate #Diagonal #Liquid crystal #Phase (matter) #Phase transition #Physics of Superconductivity and Magnetism #Pseudogap #Tetragonal crystal system #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.1038/s41467-019-11200-1
published in Nature Communications 10(1), 3282 (Nature Portfolio) · 7 pages, 8 figures
arxiv created 2018/05/01 · openalex created_date 2018/05/07 · openalex publication_date 2019/07/23 · arxiv updated 2019/07/30 · openalex updated_date 2026/08/06
Abstract The pseudogap phenomenon in the cuprates is arguably the most mysterious puzzle in the field of high-temperature superconductivity. The tetragonal cuprate HgBa 2 CuO 4+ δ , with only one CuO 2 layer per primitive cell, is an ideal system to tackle this puzzle. Here, we measure the magnetic susceptibility anisotropy within the CuO 2 plane with exceptionally high-precision magnetic torque experiments. Our key finding is that a distinct two-fold in-plane anisotropy sets in below the pseudogap temperature T * , which provides thermodynamic evidence for a nematic phase transition with broken four-fold symmetry. Surprisingly, the nematic director orients along the diagonal direction of the CuO 2 square lattice, in sharp contrast to the bond nematicity along the Cu-O-Cu direction. Another remarkable feature is that the enhancement of the diagonal nematicity with decreasing temperature is suppressed around the temperature at which short-range charge-density-wave formation occurs. Our result suggests a competing relationship between diagonal nematic and charge-density-wave order in HgBa 2 CuO 4+ δ .