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arXiv · 2602.17057

Role of atomic vacancies and second-neighbor antiferromagnetic-exchange coupling in a ferromagnetic nanoparticle

Harun Al Rashid·Muskan Sharma·Shruti·Dheeraj Kumar Singh
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Abstract

Several factors may be responsible for disorder and frustration in a magnetic nanoparticle, including atomic vacancies on the surface and inside, impurity atoms, long-range magnetic exchange coupling, etc. We use Monte-Carlo simulations within the Heisenberg model to examine the role of randomly distributed atomic vacancies and long-range magnetic-exchange coupling on the temperature-dependent magnetic properties of ferromagnetic nanoparticles. In particular, we study the role of the second-neighbor antiferromagnetic exchange coupling and missing atoms inside the particle resulting in broken nearby bonds. We find that both factors may enhance the superparamagnetic behaviors of such particles.

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Harun Al Rashid, Muskan Sharma, Shruti, Dheeraj Kumar Singh. 2026-02-19. Role of atomic vacancies and second-neighbor antiferromagnetic-exchange coupling in a ferromagnetic nanoparticle. https://doi.org/10.1007/s00339-025-08265-9

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