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Unconventional relaxation in antiferromagnetic CoRh$_2$O$_4$ nanoparticles

R. N. Bhowmik·R. Ranganathan
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Abstract

Magnetic relaxation in antiferromagnetic CoRh$_2$O$_4$ nanoparticles is investigated at 2 K by cooling the sample from a temperature (70 K) well above the antiferromagnetic ordering temperature at 27 K, following zero field cooled (ZFC) and field cooled (FC) process. In ZFC process, the sample at 2 K is subsequently followed by magnetic field on and off sequences, whereas in FC process the cooling field is made off during measurement of remanent magnetization as a function of time. The experiments suggest an unconventional relaxation behaviour in the system, as an effect of increasing surface exchange anisotropy with decreasing the size of antiferromagnetic nanoparticles.

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R. N. Bhowmik, R. Ranganathan. 2006-10-17. Unconventional relaxation in antiferromagnetic CoRh$_2$O$_4$ nanoparticles. https://doi.org/10.1103/physrevb.75.012410

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