Dual instability of superconductivity from oxygen defects in La$_3$Ni$_2$O$_{7+δ}$

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Jiang, Peiheng, Li, Jie, Cao, Yu-Han, Cao, Xiaodong, Zhong, Zhicheng, Lu, Yi, Wang, Qiang-Hua
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866918224056025088
author Jiang, Peiheng
Li, Jie
Cao, Yu-Han
Cao, Xiaodong
Zhong, Zhicheng
Lu, Yi
Wang, Qiang-Hua
author_facet Jiang, Peiheng
Li, Jie
Cao, Yu-Han
Cao, Xiaodong
Zhong, Zhicheng
Lu, Yi
Wang, Qiang-Hua
contents We uncover a dual mechanism by which oxygen defects suppress superconductivity in the bilayer nickelate La$_3$Ni$_2$O$_{7+δ}$ using density functional theory, dynamical mean-field theory, and functional renormalization group analysis. Apical vacancies and interbilayer interstitials emerge as the dominant low-energy defect species and are further stabilized by orthorhombic domain walls. These two defect classes drive the electronic structure in opposing directions. Vacancy-induced disorder generates local magnetic moments and promotes Anderson localization at moderate concentrations, whereas periodic interstitial ordering yields a coherent but weakly correlated metallic background that fails to support superconductivity. These findings highlight the decisive role of oxygen defects in shaping the superconducting and provide microscopic guidance for improving superconductivity through controlled defect engineering.
format Preprint
id arxiv_https___arxiv_org_abs_2512_00301
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Dual instability of superconductivity from oxygen defects in La$_3$Ni$_2$O$_{7+δ}$
Jiang, Peiheng
Li, Jie
Cao, Yu-Han
Cao, Xiaodong
Zhong, Zhicheng
Lu, Yi
Wang, Qiang-Hua
Superconductivity
Strongly Correlated Electrons
We uncover a dual mechanism by which oxygen defects suppress superconductivity in the bilayer nickelate La$_3$Ni$_2$O$_{7+δ}$ using density functional theory, dynamical mean-field theory, and functional renormalization group analysis. Apical vacancies and interbilayer interstitials emerge as the dominant low-energy defect species and are further stabilized by orthorhombic domain walls. These two defect classes drive the electronic structure in opposing directions. Vacancy-induced disorder generates local magnetic moments and promotes Anderson localization at moderate concentrations, whereas periodic interstitial ordering yields a coherent but weakly correlated metallic background that fails to support superconductivity. These findings highlight the decisive role of oxygen defects in shaping the superconducting and provide microscopic guidance for improving superconductivity through controlled defect engineering.
title Dual instability of superconductivity from oxygen defects in La$_3$Ni$_2$O$_{7+δ}$
topic Superconductivity
Strongly Correlated Electrons
url https://arxiv.org/abs/2512.00301