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Updated: Oct 25, 2025
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Atomic Layer Deposition of Vanadium Dioxide and a Temperature-dependent Optical Model
Published on: May 23, 2018
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Quantitative hyperspectral coherent diffractive imaging spectroscopy of a solid-state phase transition in vanadium
Allan S Johnson1, Jordi Valls Conesa2, Luciana Vidas2
1ICFO-Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, Barcelona, Spain. allan.johnson@icfo.eu simon.wall@phys.au.dk.
Science Advances
|August 12, 2021
Summary
Coherent diffractive imaging spectroscopy (CDIS) provides nanoscale insights into quantum materials like vanadium dioxide (VO2). This technique reveals distinct insulating and conducting phases without evidence of correlation-driven transitions.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spectroscopy
Background:
- Solid-state systems exhibit diverse thermodynamic phases, often nanoscale and coexisting.
- Studying these nanoscale phases requires high spatial resolution and spectroscopic data, challenging traditional methods.
- Vanadium dioxide (VO2) is a prototypical quantum material with distinct phases.
Purpose of the Study:
- To apply coherent diffractive imaging spectroscopy (CDIS) for nanoscale phase analysis in VO2.
- To obtain quantitative hyperspectral images of VO2 phases.
- To investigate the nature of phase transitions in VO2.
Main Methods:
- Utilized coherent diffractive imaging spectroscopy (CDIS).
- Acquired hyperspectral images at vanadium L2,3 and oxygen K x-ray absorption edges.
- Achieved nanometer-scale spatial resolution.
Main Results:
- Successfully extracted complex refractive indices for monoclinic insulating and rutile conducting phases of VO2.
- Analyzed a single sample to characterize coexisting phases.
- Found no evidence supporting correlation-driven phase transitions in VO2.
Conclusions:
- CDIS enables quantitative, full-field x-ray spectromicroscopy at the nanoscale.
- The technique is suitable for studying phase separation in challenging experimental conditions.
- The findings contribute to understanding phase behavior in quantum materials like VO2.
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