Title: Ultralow blocking temperature and breakdown of the giant spin model in Er3+-doped nanoparticles
Authors: Van den Heuvel, Willem
Tikhomirov, Victor
Kirilenko, D
Schildermans, N
Chibotaru, Liviu ×
Vanacken, Johan
Gredin, P
Mortier, M
van Tendeloo, G
Moshchalkov, Victor #
Issue Date: Sep-2010
Publisher: Published by the American Physical Society through the American Institute of Physics
Series Title: Physical Review B, Condensed Matter and Materials Physics vol:82 issue:9 pages:1-8
Article number: 094421
Abstract: The magnetization of luminescent Er3+-doped PbF2 nanoparticles (formula Er0.3Pb0.7F2.3) has been studied. Despite the high concentration of the doping Er3+ ions and relatively large size (8 nm) of these nanoparticles we have found no deviation between field-cooled and zero-field-cooled magnetization curves down to T = 0.35 K, which points out an ultralow blocking temperature for the reversal of magnetization. We also have found strongly deviating magnetization curves M(H/T) for different temperatures T. These results altogether show that the investigated nanoparticles are not superparamagnetic, but rather each Er3+ ion in these nanoparticles is found in a paramagnetic state down to very low temperatures, which implies the breakdown of the Neel-Brown giant spin model in the case of these nanoparticles. Calculations of magnetization within a paramagnetic model of noninteracting Er3+ ions completely support this conclusion. Due to the ultralow blocking temperature, these nanoparticles have a potential for magnetic field-induced nanoscale refrigeration with an option of their optical localization and temperature control.
ISSN: 1098-0121
Publication status: published
KU Leuven publication type: IT
Appears in Collections:Quantum Chemistry and Physical Chemistry Section
Solid State Physics and Magnetism Section
× corresponding author
# (joint) last author

Files in This Item:

There are no files associated with this item.

Request a copy


All items in Lirias are protected by copyright, with all rights reserved.

© Web of science