Journal article
Nanocriticality in the magnetic phase transition of CoO nanoparticles
University of Copenhagen1
Risø National Laboratory for Sustainable Energy, Technical University of Denmark2
Neutrons and X-rays for Materials Physics, Department of Physics, Technical University of Denmark3
Department of Physics, Technical University of Denmark4
Paul Scherrer Institute5
Imaging and Structural Analysis, Department of Energy Conversion and Storage, Technical University of Denmark6
Department of Energy Conversion and Storage, Technical University of Denmark7
The universal theory of critical phase transitions describes the critical behavior at second-order phase transitions in infinitely large systems. With the increased contemporary interest in nanoscale materials, we investigated CoO nanoparticles by means of neutron scattering and found how the theory of critical phenomena breaks down in the nanoscale regime.
Using CoO as a model system, we have identified a size-dependent nanocritical temperature region close to the antiferromagnetic phase transition where the magnetic correlation length of the nanoparticles converges to a constant value, which is significantly smaller than that of the saturated state found at low temperatures.
This is in clear contrast to the divergence around TN observed for bulk systems. Our finding of nanocriticality in the magnetic phase transition is of great importance for the understanding of phase transitions at the nanoscale.
Language: | English |
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Year: | 2023 |
ISSN: | 1550235x , 10980121 and 24699950 |
Types: | Journal article |
DOI: | 10.1103/PhysRevB.107.064424 |
ORCIDs: | 0000-0002-7128-4149 , 0000-0001-6311-9568 , 0000-0003-4282-756X , Christensen, Niels B. , Kuhn, Luise Theil and Frandsen, Cathrine |