open access

https://hdl.handle.net/2115/81979

Fermi surface in La-based cuprate superconductors from Compton scattering imaging

英語

2021-04-13

Nature Research

Nature communications

12(1)

2223

Compton scattering provides invaluable information on the underlying Fermi surface (FS) and is a powerful tool complementary to angle-resolved photoemission spectroscopy and quantum oscillation measurements. Here we perform high-resolution Compton scattering measurements for La2-xSrxCuO4 with x=0.08 (T-c=20 K) at 300 K and 150 K, and image the momentum distribution function in the two-dimensional Brillouin zone. We find that the observed images cannot be reconciled with the conventional hole-like FS believed so far. Instead, our data imply that the FS is strongly deformed by the underlying nematicity in each CuO2 plane, but the bulk FSs recover the fourfold symmetry. We also find an unusually strong temperature dependence of the momentum distribution function, which may originate from the pseudogap formation in the presence of the reconstructed FSs due to the underlying nematicity. Additional measurements for x=0.15 and 0.30 at 300 K suggest similar FS deformation with weaker nematicity, which nearly vanishes at x=0.30. Compton scattering provides information on the Fermi surface (FS) hence very useful to understand the electronic structure of high temperature superconductors. Here, Yamase et al. perform Compton scattering measurements on La2-xSrxCuO4 samples and observe deformed FS in CuO2 plane due to nematicity but recovering fourfold symmetry in bulk FS.

学術雑誌論文

Version of Record

2041-1723