---
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'
...
---
_id: '5816'
abstract:
- lang: eng
  text: Solid-state qubit manipulation and read-out fidelities are reaching fault-tolerance,
    but quantum error correction requires millions of physical qubits and therefore
    a scalable quantum computer architecture. To solve signal-line bandwidth and fan-out
    problems, microwave sources required for qubit manipulation might be embedded
    close to the qubit chip, typically operating at temperatures below 4 K. Here,
    we perform the first low temperature measurements of a 130 nm BiCMOS based SiGe
    voltage controlled oscillator at cryogenic temperature. We determined the frequency
    and output power dependence on temperature and magnetic field up to 5 T and measured
    the temperature influence on its noise performance. The device maintains its full
    functionality from 300 K to 4 K. The carrier frequency at 4 K increases by 3%
    with respect to the carrier frequency at 300 K, and the output power at 4 K increases
    by 10 dB relative to the output power at 300 K. The frequency tuning range of
    approximately 20% remains unchanged between 300 K and 4 K. In an in-plane magnetic
    field of 5 T, the carrier frequency shifts by only 0.02% compared to the frequency
    at zero magnetic field.
article_number: '114701'
article_processing_charge: No
arxiv: 1
author:
- first_name: Arne
  full_name: Hollmann, Arne
  last_name: Hollmann
- first_name: Daniel
  full_name: Jirovec, Daniel
  id: 4C473F58-F248-11E8-B48F-1D18A9856A87
  last_name: Jirovec
  orcid: 0000-0002-7197-4801
- first_name: Maciej
  full_name: Kucharski, Maciej
  last_name: Kucharski
- first_name: Dietmar
  full_name: Kissinger, Dietmar
  last_name: Kissinger
- first_name: Gunter
  full_name: Fischer, Gunter
  last_name: Fischer
- first_name: Lars R.
  full_name: Schreiber, Lars R.
  last_name: Schreiber
citation:
  ama: Hollmann A, Jirovec D, Kucharski M, Kissinger D, Fischer G, Schreiber LR. 30
    GHz-voltage controlled oscillator operating at 4 K. <i>Review of Scientific Instruments</i>.
    2018;89(11). doi:<a href="https://doi.org/10.1063/1.5038258">10.1063/1.5038258</a>
  apa: Hollmann, A., Jirovec, D., Kucharski, M., Kissinger, D., Fischer, G., &#38;
    Schreiber, L. R. (2018). 30 GHz-voltage controlled oscillator operating at 4 K.
    <i>Review of Scientific Instruments</i>. AIP Publishing. <a href="https://doi.org/10.1063/1.5038258">https://doi.org/10.1063/1.5038258</a>
  chicago: Hollmann, Arne, Daniel Jirovec, Maciej Kucharski, Dietmar Kissinger, Gunter
    Fischer, and Lars R. Schreiber. “30 GHz-Voltage Controlled Oscillator Operating
    at 4 K.” <i>Review of Scientific Instruments</i>. AIP Publishing, 2018. <a href="https://doi.org/10.1063/1.5038258">https://doi.org/10.1063/1.5038258</a>.
  ieee: A. Hollmann, D. Jirovec, M. Kucharski, D. Kissinger, G. Fischer, and L. R.
    Schreiber, “30 GHz-voltage controlled oscillator operating at 4 K,” <i>Review
    of Scientific Instruments</i>, vol. 89, no. 11. AIP Publishing, 2018.
  ista: Hollmann A, Jirovec D, Kucharski M, Kissinger D, Fischer G, Schreiber LR.
    2018. 30 GHz-voltage controlled oscillator operating at 4 K. Review of Scientific
    Instruments. 89(11), 114701.
  mla: Hollmann, Arne, et al. “30 GHz-Voltage Controlled Oscillator Operating at 4
    K.” <i>Review of Scientific Instruments</i>, vol. 89, no. 11, 114701, AIP Publishing,
    2018, doi:<a href="https://doi.org/10.1063/1.5038258">10.1063/1.5038258</a>.
  short: A. Hollmann, D. Jirovec, M. Kucharski, D. Kissinger, G. Fischer, L.R. Schreiber,
    Review of Scientific Instruments 89 (2018).
date_created: 2019-01-10T14:22:23Z
date_published: 2018-11-01T00:00:00Z
date_updated: 2026-08-13T22:30:45Z
day: '01'
department:
- _id: GeKa
doi: 10.1063/1.5038258
external_id:
  arxiv:
  - '1804.09522'
  isi:
  - '000451735700054'
intvolume: '        89'
isi: 1
issue: '11'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1804.09522
month: '11'
oa: 1
oa_version: Preprint
publication: Review of Scientific Instruments
publication_identifier:
  issn:
  - 0034-6748
publication_status: published
publisher: AIP Publishing
quality_controlled: '1'
related_material:
  record:
  - id: '10058'
    relation: dissertation_contains
    status: public
scopus_import: '1'
status: public
title: 30 GHz-voltage controlled oscillator operating at 4 K
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 89
year: '2018'
...