Correlated Electronic Structure and Density-Wave Gap in Trilayer Nickelate La4Ni3O10

TL;DR

This study investigates the electronic structure of La4Ni3O10, revealing a density-wave gap and similarities with La3Ni2O7, providing insights into the superconductivity mechanisms in nickelates through combined experimental and theoretical analysis.

Contribution

It offers the first detailed analysis of La4Ni3O10's electronic structure at ambient pressure, highlighting density-wave transition and electronic correlations relevant to superconductivity.

Findings

Orbital-dependent energy gap linked to density-wave transition.

High resemblance of La4Ni3O10's electronic structure to La3Ni2O7.

Insights into high-pressure superconducting phases from ambient measurements.

Abstract

The discovery of pressurized superconductivity at 80 K in La3Ni2O7 officially brings nickelates into the family of high-temperature superconductors, which gives rise to not only new insights but also mysteries in the strongly correlated superconductivity. More recently, the sibling compound La4Ni3O10 was also shown to be superconducting below about 25 K under pressure, further boosting the popularity of nickelates in the Ruddlesden-Popper phase. In this study, combining high-resolution angle-resolved photoemission spectroscopy and ab initio calculation, we systematically investigate the electronic structures of La4Ni3O10 at ambient pressure. We reveal a high resemblance of La4Ni3O10 with La3Ni2O7 in the orbital-dependent fermiology and electronic structure, suggesting a similar electronic correlation between the two compounds. The temperature-dependent measurements imply an orbital-dependent energy gap related to the density-wave transition in La4Ni3O10. By comparing the theoretical pressure-dependent electronic structure, clues about the superconducting high-pressure phase can be deduced from the ambient measurements, providing crucial information for deciphering the unconventional superconductivity in nickelates.