8 January 2013 Thermodynamics of antiferromagnetic nanoparticles and macroscopic quantum effects observed by Mössbauer spectroscopy
Author Affiliations +
Proceedings Volume 8700, International Conference Micro- and Nano-Electronics 2012; 87000F (2013) https://doi.org/10.1117/12.2016920
Event: International Conference on Micro-and Nano-Electronics 2012, 2012, Zvenlgorod, Russian Federation
Abstract
A quantum-mechanical model for describing thermodynamic properties of an ensemble of ideal antiferromagnetic nanoparticles with axial magnetic anisotropy is developed in the first approximation of slowly relaxing macrospins of magnetic sublattices. This model clarifies principally the difference in thermodynamic behavior of ferromagnetic and antiferromagnetic particles revealed in spectroscopic measurements. In particular, one can now qualitatively describe specific (non-superparamagnetic) temperature evolution of the 57Fe Mössbauer spectra of antiferromagnetic nanoparticles, which has been often observed for almost half a century and looks like a quantum superposition of well resolved magnetic hyperfine structure and single line (or quadrupolar doublet of lines) with the temperature-dependent partial spectral areas. This approach can be easily generalized for describing uncompensated antiferromagnetic and ferrimagnetic nanoparticles as well as magnetic relaxation processes, which would allow one to take directly into account the magnetic nature inherent to the particles in analyzing a large amount of experimental data collected so far.
© (2013) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Mikhail A. Chuev, Mikhail A. Chuev, } "Thermodynamics of antiferromagnetic nanoparticles and macroscopic quantum effects observed by Mössbauer spectroscopy", Proc. SPIE 8700, International Conference Micro- and Nano-Electronics 2012, 87000F (8 January 2013); doi: 10.1117/12.2016920; https://doi.org/10.1117/12.2016920
PROCEEDINGS
12 PAGES


SHARE
Back to Top