---
OA_place: publisher
OA_type: hybrid
_id: '19828'
abstract:
- lang: eng
  text: 'We describe an optical method to directly measure the position-dependent
    thermal diffusivity of reflective single crystal samples across a broad range
    of temperatures for condensed matter physics research. Two laser beams are used,
    one as a source to locally modulate the sample temperature, and the other as a
    probe of sample reflectivity, which is a function of the modulated temperature.
    Thermal diffusivity is obtained from the phase delay between source and probe
    signals. We combine this technique with a microscope setup in an optical cryostat,
    in which the sample is placed on a three-axis piezo-stage, allowing for spatially
    resolved measurements. Furthermore, we demonstrate experimentally and mathematically
    that isotropic in-plane diffusivity can be obtained when overlapping the two laser
    beams instead of separating them in the traditional way, which further enhances
    the spatial resolution to a micron scale, especially valuable when studying inhomogeneous
    or multidomain samples. We discuss in detail the experimental conditions under
    which this technique is valuable and demonstrate its performance on two stoichiometric
    bilayer ruthenates: Sr3Ru2O7 and Ca3Ru2O7. The spatial resolution allowed us to
    study the diffusivity in single domains of the latter, and we uncovered a temperature-dependent
    in-plane diffusivity anisotropy. Finally, we used the enhanced spatial resolution
    enabled by overlapping the two beams to measure the temperature-dependent diffusivity
    of Ti-doped Ca3Ru2O7, which exhibits a metal–insulator transition. We observed
    large variations of transition temperature over the same sample, originating from
    doping inhomogeneity and pointing to the power of spatially resolved techniques
    in accessing inherent properties.'
article_number: '043003'
article_processing_charge: Yes (in subscription journal)
article_type: original
arxiv: 1
author:
- first_name: F.
  full_name: Sun, F.
  last_name: Sun
- first_name: S.
  full_name: Mishra, S.
  last_name: Mishra
- first_name: P. H.
  full_name: McGuinness, P. H.
  last_name: McGuinness
- first_name: Z. H.
  full_name: Filipiak, Z. H.
  last_name: Filipiak
- first_name: I.
  full_name: Marković, I.
  last_name: Marković
- first_name: D. A.
  full_name: Sokolov, D. A.
  last_name: Sokolov
- first_name: N.
  full_name: Kikugawa, N.
  last_name: Kikugawa
- first_name: J. W.
  full_name: Orenstein, J. W.
  last_name: Orenstein
- first_name: S. A.
  full_name: Hartnoll, S. A.
  last_name: Hartnoll
- first_name: A. P.
  full_name: Mackenzie, A. P.
  last_name: Mackenzie
- first_name: Veronika
  full_name: Sunko, Veronika
  id: 23cb1cf6-2c7a-11ef-91a4-f72fc19f20b3
  last_name: Sunko
  orcid: 0000-0003-2724-3523
citation:
  ama: Sun F, Mishra S, McGuinness PH, et al. A spatially resolved optical method
    to measure thermal diffusivity. <i>Review of Scientific Instruments</i>. 2023;94(4).
    doi:<a href="https://doi.org/10.1063/5.0098800">10.1063/5.0098800</a>
  apa: Sun, F., Mishra, S., McGuinness, P. H., Filipiak, Z. H., Marković, I., Sokolov,
    D. A., … Sunko, V. (2023). A spatially resolved optical method to measure thermal
    diffusivity. <i>Review of Scientific Instruments</i>. AIP Publishing. <a href="https://doi.org/10.1063/5.0098800">https://doi.org/10.1063/5.0098800</a>
  chicago: Sun, F., S. Mishra, P. H. McGuinness, Z. H. Filipiak, I. Marković, D. A.
    Sokolov, N. Kikugawa, et al. “A Spatially Resolved Optical Method to Measure Thermal
    Diffusivity.” <i>Review of Scientific Instruments</i>. AIP Publishing, 2023. <a
    href="https://doi.org/10.1063/5.0098800">https://doi.org/10.1063/5.0098800</a>.
  ieee: F. Sun <i>et al.</i>, “A spatially resolved optical method to measure thermal
    diffusivity,” <i>Review of Scientific Instruments</i>, vol. 94, no. 4. AIP Publishing,
    2023.
  ista: Sun F, Mishra S, McGuinness PH, Filipiak ZH, Marković I, Sokolov DA, Kikugawa
    N, Orenstein JW, Hartnoll SA, Mackenzie AP, Sunko V. 2023. A spatially resolved
    optical method to measure thermal diffusivity. Review of Scientific Instruments.
    94(4), 043003.
  mla: Sun, F., et al. “A Spatially Resolved Optical Method to Measure Thermal Diffusivity.”
    <i>Review of Scientific Instruments</i>, vol. 94, no. 4, 043003, AIP Publishing,
    2023, doi:<a href="https://doi.org/10.1063/5.0098800">10.1063/5.0098800</a>.
  short: F. Sun, S. Mishra, P.H. McGuinness, Z.H. Filipiak, I. Marković, D.A. Sokolov,
    N. Kikugawa, J.W. Orenstein, S.A. Hartnoll, A.P. Mackenzie, V. Sunko, Review of
    Scientific Instruments 94 (2023).
date_created: 2025-06-10T09:23:29Z
date_published: 2023-04-10T00:00:00Z
date_updated: 2025-06-11T06:14:06Z
day: '10'
ddc:
- '530'
doi: 10.1063/5.0098800
extern: '1'
external_id:
  arxiv:
  - '2303.02017'
  pmid:
  - '38081228'
has_accepted_license: '1'
intvolume: '        94'
issue: '4'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.1063/5.0098800
month: '04'
oa: 1
oa_version: Published Version
pmid: 1
publication: Review of Scientific Instruments
publication_identifier:
  eissn:
  - 1089-7623
  issn:
  - 0034-6748
publication_status: published
publisher: AIP Publishing
quality_controlled: '1'
related_material:
  link:
  - relation: erratum
    url: https://doi.org/10.1063/5.0195810
scopus_import: '1'
status: public
title: A spatially resolved optical method to measure thermal diffusivity
tmp:
  image: /images/cc_by.png
  legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode
  name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)
  short: CC BY (4.0)
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 94
year: '2023'
...