# Correlated Insulator at the Surface of the Polar Metal                    <math display="inline">                      <mrow>                        <mrow>                          <msub>                            <mrow>                              <mi>Ca</mi>                            </mrow>                            <mrow>                              <mn>3</mn>                            </mrow>                          </msub>                        </mrow>                        <msub>                          <mrow>                            <mtext>Ru</mtext>                          </mrow>                          <mrow>                            <mn>2</mn>                          </mrow>                        </msub>                        <msub>                          <mrow>                            <mi>O</mi>                          </mrow>                          <mrow>                            <mn>7</mn>                          </mrow>                        </msub>                      </mrow>                    </math>

https://mdr.nims.go.jp/datasets/af36ca5b-690b-4cf3-ba63-eff27a91ae0e

## File

- [2603.23657v2.pdf](https://mdr.nims.go.jp/filesets/f0fe9a7d-57e1-4a89-a88e-e6c8d6b0e90b/download) ([Detail](https://mdr.nims.go.jp/filesets/f0fe9a7d-57e1-4a89-a88e-e6c8d6b0e90b.md))

## Id

af36ca5b-690b-4cf3-ba63-eff27a91ae0e

## Local identifier



## Visibility

open_to_public

## State

published

## Created at

2026-08-26T21:56:13.809733Z

## Updated at

2026-08-26T23:47:50.521412Z

## Published at

2026-08-27T01:26:21.948005Z

## Doi



## First published url

https://doi.org/10.1103/x9gh-xxwb

## Date published

2026-08-26

## Recorded date published

2026-8

## Resource type

journal_article

## Manuscript type

authors_original

## Collection



## Title

- title: |-
    Correlated Insulator at the Surface of the Polar Metal
                        <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline">
                          <mml:mrow>
                            <mml:mrow>
                              <mml:msub>
                                <mml:mrow>
                                  <mml:mi>Ca</mml:mi>
                                </mml:mrow>
                                <mml:mrow>
                                  <mml:mn>3</mml:mn>
                                </mml:mrow>
                              </mml:msub>
                            </mml:mrow>
                            <mml:msub>
                              <mml:mrow>
                                <mml:mtext>Ru</mml:mtext>
                              </mml:mrow>
                              <mml:mrow>
                                <mml:mn>2</mml:mn>
                              </mml:mrow>
                            </mml:msub>
                            <mml:msub>
                              <mml:mrow>
                                <mml:mi mathvariant="normal">O</mml:mi>
                              </mml:mrow>
                              <mml:mrow>
                                <mml:mn>7</mml:mn>
                              </mml:mrow>
                            </mml:msub>
                          </mml:mrow>
                        </mml:math>
  title_type: original
  lang: en

## Description

- description: 'We investigate the electronic structure at the surface of the correlated
    oxide Ca3Ru2O7, a low-symmetry ruthenate oxide which hosts an unconventional polar-metal
    phase. From a combination of angle-resolved photoemission spectroscopy and scanning
    tunneling spectroscopy measurements, we demonstrate that the surface hosts an
    insulating phase, a distinct departure from metallicity within the bulk. Utilizing
    quantitative low-energy electron diffraction in conjunction with electronic structure
    calculations, we show how this results from a combined surface structure relaxation
    and the impact of marked electronic correlations in this system. Our findings
    highlight the proximity of Ca3Ru2O7 to an insulating metallic state, and illustrate
    how subtle structural distortions can control its emergent electronic phases. '
  description_type: abstract
  lang: und

## Creator

- name: Daniel Halliday
  role: author
  orcid: https://orcid.org/0009-0007-0653-8759
- name: Izidor Benedičič
  role: author
  orcid: https://orcid.org/0000-0003-4841-9495
- name: Andela Zivanovic
  role: author
  orcid: https://orcid.org/0009-0006-8164-7085
- name: Masahiro Naritsuka
  role: author
  orcid: https://orcid.org/0000-0001-9774-8645
- name: Brendan Edwards
  role: author
  orcid: https://orcid.org/0000-0002-7219-4241
- name: Tommaso Antonelli
  role: author
- name: Naoki Kikugawa
  role: author
  orcid: https://orcid.org/0000-0003-3975-4478
- name: Dmitry A. Sokolov
  role: author
- name: Craig Polley
  role: author
- name: Andrew P. Mackenzie
  role: author
- name: Georg Held
  role: author
  orcid: https://orcid.org/0000-0003-0726-4183
- name: Phil D. C. King
  role: author
  orcid: https://orcid.org/0000-0002-6523-9034
- name: Peter Wahl
  role: author
  orcid: https://orcid.org/0000-0002-8635-1519

## Contact agent



## Publisher

organization: American Physical Society (APS)

## Managing organization



## Keyword

- subject: Ca3Ru2P7
  schema: not_defined
- subject: STM/STS
  schema: not_defined

## Rights

- identifier: http://arxiv.org/licenses/nonexclusive-distrib/1.0/

## Other identifier(s)



## Data origin



## Embargo



## Journal

- title: Physical Review Letters
  issn: '00319007'
  volume: '137'
  issue: '9'
  article_number: '096503'

## Conference



## Related item



## Funding

- identifier: RL-2016-006
  funder_name: Leverhulme Trust
- identifier: RPG-2022-315
  funder_name: Leverhulme Trust
- funder_name: Diamond Light Source
- funder_name: International Max Planck Research School for Chemistry and Physics
    of Quantum Materials
- identifier: 2018-07152
  funder_name: Vetenskapsrådet
- identifier: 2018-04969
  funder_name: VINNOVA
- identifier: 2019-02496
  funder_name: Svenska Forskningsrådet Formas
- identifier: 24K01461
  funder_name: Japan Society for the Promotion of Science
- funder_name: University of Edinburgh
- funder_name: UK Research and Innovation
- funder_name: Engineering and Physical Sciences Research Council

## Instrument



## Instrument operator



## Instrument managing organization



## Measurement method



## Specimen



## Chemical composition



## Structure for specimen



## Structural feature for specimen



## Specific property for specimen



## Process for specimen treatment



## Computational method



## Energy level/transition state



## Software



## Custom property



## Fileset

- id: f0fe9a7d-57e1-4a89-a88e-e6c8d6b0e90b
  filename: 2603.23657v2.pdf
  content_type: application/pdf
  size: 9894255
  md5: b8701c568fbcaf8e1e6cd86650f4eeab

## Thumbnail

fileset_id: f0fe9a7d-57e1-4a89-a88e-e6c8d6b0e90b
filename: 2603.23657v2.pdf