Abstract
High temperature superconductivity was recently found in the bilayer nickelate (La327), followed by the discovery of superconductivity in the trilayer (La4310), under high pressure. Through studying the electronic correlation of La4310 with , and further comparing it with that of La327, we find that the orbitals of the outer-layer Ni cations in La4310 have a similar (but slightly weaker) electronic correlation to those in La327, in which the electrons behave as a non-Fermi liquid with Hund correlation and linear-in-temperature scattering rate. Our results suggest that the experimentally observed “strange metal” behavior may be explained by the Hund spin correlation featuring high spin states and spin-orbital separation. In contrast, the electrons in the inner-layer Ni cations in La4310 behave as a Fermi liquid. The weaker electronic correlation in La4310 is attributed to more hole doping, which may explain its lower superconducting transition temperature.
- Received 6 February 2024
- Accepted 3 April 2024
DOI:https://doi.org/10.1103/PhysRevB.109.165140
©2024 American Physical Society