Quantum tunneling of magnetization in single domain CoFe2O4 particles

T. Oku, H. Takano, M. Ohwada, Tetsuya Sato, E. Ohta

Research output: Chapter in Book/Report/Conference proceedingChapter

Abstract

We systematically investigated the macroscopic quantum tunneling (MQT) phenomena of magnetization in CoFe2O4 particles with a diameter ranging from 30 to 92 Å in zero external magnetic field to remove the substantial influence of energy dissipation. For all of our samples, we observed the MQT phenomena in zero external magnetic field, in spite of the anticipation that a large magnetic field H comparable with the coercive force Hc would be necessary to lower the energy barrier so as to observe appreciable quantum tunneling of magnetization. The analysis shows that the crossover temperature T from the thermal to the quantum regime increases with decreasing anisotropy field HA. This relation between T* and HA is inconsistent with the theoretical prediction.

Original languageEnglish
Title of host publicationJournal De Physique. IV : JP
Volume7
Edition1
Publication statusPublished - 1997 Mar

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magnetization
magnetic fields
crossovers
energy dissipation
anisotropy
predictions
temperature
energy

ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this

Oku, T., Takano, H., Ohwada, M., Sato, T., & Ohta, E. (1997). Quantum tunneling of magnetization in single domain CoFe2O4 particles. In Journal De Physique. IV : JP (1 ed., Vol. 7)

Quantum tunneling of magnetization in single domain CoFe2O4 particles. / Oku, T.; Takano, H.; Ohwada, M.; Sato, Tetsuya; Ohta, E.

Journal De Physique. IV : JP. Vol. 7 1. ed. 1997.

Research output: Chapter in Book/Report/Conference proceedingChapter

Oku, T, Takano, H, Ohwada, M, Sato, T & Ohta, E 1997, Quantum tunneling of magnetization in single domain CoFe2O4 particles. in Journal De Physique. IV : JP. 1 edn, vol. 7.
Oku T, Takano H, Ohwada M, Sato T, Ohta E. Quantum tunneling of magnetization in single domain CoFe2O4 particles. In Journal De Physique. IV : JP. 1 ed. Vol. 7. 1997
Oku, T. ; Takano, H. ; Ohwada, M. ; Sato, Tetsuya ; Ohta, E. / Quantum tunneling of magnetization in single domain CoFe2O4 particles. Journal De Physique. IV : JP. Vol. 7 1. ed. 1997.
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