PC11-5
Electronic nematic Fermi surface in La-based cuprates from Compton scattering imaging
Hiroyuki Yamase1,2, Yoshiharu Sakurai3, Masaki Fujita4, Shunichi Wakimoto5, Kazuyoshi Yamada6
- International Center for Materials Nanoarchitectonics, National Institute for Materials Science (NIMS)1
- Department of Condensed Matter Physics, Graduate School of Science, Hokkaido University2
- Japan Synchrotron Radiation Research Institute (JASRI), SPring-83
- Institute for Materials Research, Tohoku University4
- Materials Sciences Research Center, Japan Atomic Energy Agency5
- High Energy Accelerator Research Organization (KEK)6
Compton scattering can image the electron momentum distribution function directly in the whole Brillouin zone and provide invaluable information on the underlying Fermi surface (FS).
In contrast to angle-resolved photoemission spectroscopy, it is bulk sensitive and more crucially it does not suffer from a matrix-element effect.
Here we report high-resolution Compton scattering measurements for La2-xSrxCuO4 with x = 0.08 (Tc = 20 K) at 300 K and 150 K, and image the momentum distribution function in the two-dimensional Brillouin zone [1]. 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.
Figure 1: Compton scattering image of the momentum distribution function in the first Brillouin zone at 300 K for La2-xSrxCuO4 with x = 0.08. The square around k = (0,0) contains a large experimental error and thus should not be considered.
[1] H. Yamase, Y. Sakurai, M. Fujita, S. Wakimoto, and K. Yamada, Nat. Commun. 12, 2223 (2021).
