superparamagnetism

physics

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July 14, 2026

Quick Summary

Superparamagnetism is a type of magnetism that occurs in materials with very small grains, typically around 100 angstroms. In these materials, the thermal energy is sufficient to overcome any cooperative alignment of magnetic dipole moments.1

This phenomenon is related to other types of magnetism, including:
* Diamagnetism: Materials weakly repelled by a magnetic field, present in all substances.12
* Paramagnetism: Materials weakly attracted by a magnetic field, where atomic magnetic moments tend to align with an applied field.132
* Ferromagnetism: Materials strongly attracted to magnets, where atomic magnetic moments spontaneously align even without an external field, up to a certain temperature (the Curie point).14
* Antiferromagnetism: Materials where adjacent magnetic moments align in opposite directions, canceling each other out.15
* Ferrimagnetism: A type of magnetism with antiparallel alignment of magnetic moments but with unequal moments, resulting in a net magnetism.12

Unlike ferromagnetism, superparamagnetic materials do not retain magnetization once the external magnetic field is removed.1

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nanotechnology
Magnetic, mechanical, and chemical behaviour
…16 nanometres, an effect termed superparamagnetism. Mechanical properties of nanostructured materials can reach exceptional strengths. As a specific example, the introduction of two-nanometre aluminum oxide precipitates into thin films of pure nickel results in yield strengths increasing from 0.15 to 5 gigapascals, which is more than twice that for a…
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…16 nanometres, an effect termed superparamagnetism. Mechanical properties of nanostructured materials can reach exceptional strengths. As a specific example, the introduction of two-nanometre aluminum oxide precipitates into thin films of pure nickel results in yield strengths increasing from 0.15 to 5 gigapascals, which is more than twice that for a…
Read More

rock
Basic types of magnetization
Superparamagnetism occurs in materials having grains so small (about 100 angstroms) that any cooperative alignment of dipole moments is overcome by thermal energy.
Read More
Superparamagnetism occurs in materials having grains so small (about 100 angstroms) that any cooperative alignment of dipole moments is overcome by thermal energy.
Read More