Identification of a Nematic Pair Density Wave State in Bi₂Sr₂CaCu₂O_8+x

Session

Poster Session Three

Authors

Dr. Weijiong Chen (4), Wangping Ren (4), Niall Kennedy (3, 4), Dr. Mohammad Hamidian (1), Prof. S. Uchida (5), Prof. H. Eisaki (2), Dr. Peter Johnson (4, 6), Dr. Shane O'Mahony (3), Prof. Séamus Davis (4, 3, 1, 7)

Affiliations

1. Cornell University
2. Institute of Advanced Industrial Science and Technology
3. University College Cork
4. University of Oxford
5. University of Tokyo
6. Brookhaven National Laboratory
7. Max-Planck Institute for Chemical Physics of Solids

Keywords

cuprate, nematic, pair density wave, vestigial, zinc impurity atom

Abstract text

Electron-pair density wave (PDW) states are now an intense focus of research in the field of cuprate correlated superconductivity. PDW’s exhibit periodically modulating superconductive electron pairing which can be visualized directly using scanned Josephson tunneling microscopy (SJTM). Although from theory, intertwining the d-wave superconducting (DSC) and PDW order parameters allows a plethora of global electron-pair orders to appear, which one actually occurs in the various cuprates is unknown. Here we use SJTM to visualize the interplay of PDW and DSC states in Bi₂Sr₂CaCu₂O_8+x at a carrier density where the charge density wave (CDW) modulations are virtually nonexistent. Simultaneous visualization of their amplitudes reveals that the intertwined PDW and DSC are mutually attractive states. Then, by separately imaging the electron-pair density modulations of the two orthogonal PDWs, we discover a robust nematic PDW state. Its spatial arrangement entails Ising domains of opposite nematicity. Further, we demonstrate by direct imaging that the scattering resonances identifying Zn impurity atom sites occur predominantly within boundaries between these domains. This implies that the nematic PDW state is pinned by Zn atoms, as was recently proposed (Lozano et al, PHYSICAL REVIEW B 103, L020502 (2021)). Taken in combination, these data indicate that the PDW in Bi₂Sr₂CaCu₂O_8+x is a vestigial nematic pair density wave state (J. Wardh and M. Granath arXiv:2203.08250v1).

References