First-principles study on Pr-doped Bilayer Nickelate La3Ni2O7

TL;DR

This study uses first-principles calculations to analyze how Pr-doping affects the structure and electronic properties of La3Ni2O7, providing insights into its potential to enhance superconductivity.

Contribution

It offers the first detailed computational analysis of Pr-doping effects on La3Ni2O7's structure and electronic behavior, guiding future experimental and theoretical research.

Findings

Pr atoms prefer outer La-O layers

Doping causes inconsistent structural evolution

Pr doping may enhance superconductivity

Abstract

Recently, the Pr-doped Ruddlesden-Popper phase of bilayer nickelate La3Ni2O7 has been reported to exhibit a superconducting transition temperature (Tc) of 82.5 K and superconducting volume fraction of about 57 % at high pressure. However, the effect of Pr-doping on La3Ni2O7 remains unclear. Here, we studied the crystal structures and electronic properties of Pr-doped La3Ni2O7 at 0 and 15 GPa based on the first-principles calculations to explore the doping effect of Pr. Our findings indicate that the praseodymium atoms prefer to occupy the outer La-O layers site. We then investigated the evolution of crystal structures in both the ambient pressure phase and high pressure phase of La3Ni2O7 as a function of doping concentration, revealing inconsistent trends in their evolution with increasing doping levels. Finally, by fitting the bilayer two-orbital model, we propose that doping Pr may benefit for superconductivity of La3Ni2O7. These results not only can help the further experimental search of RP phase nickelate at lower pressure, but also provide helpful guide for understanding the effect of chemical pressure in isovalent doped RP phase nickelate superconductor.