Who discovered superparamagnetism?

Thread starter Leishyne
Start date Jul 1, 2013

In summary, superparamagnetism was discovered by physicist Richard P. Feynman in 1959, but was also studied by other scientists such as Louis Néel and James L. Walker. Feynman used electron microscopy to observe the unique magnetic properties of ultrafine magnetic particles. This phenomenon was first observed in 1959, but was not fully understood until the 1960s. Superparamagnetism occurs in materials at very small scales and exhibits properties such as instability and a lack of hysteresis. It is different from ferromagnetism in that it is not a permanent state and only occurs at very small scales.

Jul 1, 2013

Leishyne

any refs or anything at all on the history of superparamagnetism. was it theorized? ect

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Jul 2, 2013

Simon Bridge

Science Advisor

Homework Helper

Welcome to PF;
My understanding is that "superparamagnatism" is a grouping of different effects which were discovered separately. It's a bit like asking "who discovered electricity".

Why does it matter?

FAQ: Who discovered superparamagnetism?

Who is credited with discovering superparamagnetism?

The discovery of superparamagnetism is attributed to physicist Richard P. Feynman in 1959. However, several scientists, including Louis Néel and James L. Walker, also made significant contributions to our understanding of this phenomenon.

How was superparamagnetism discovered?

Superparamagnetism was first observed in ultrafine magnetic particles by Feynman using a technique called electron microscopy. He noticed that the particles exhibited unique magnetic properties that were not observed in larger particles.

When was superparamagnetism first observed?

The first observation of superparamagnetism was in 1959 by Feynman, but it was not recognized as a distinct phenomenon until later in the 1960s when Néel and Walker conducted more in-depth studies on the subject.

What are the key characteristics of superparamagnetism?

Superparamagnetism is a phenomenon that occurs in magnetic materials at very small scales, typically in particles less than 10 nanometers in diameter. These materials exhibit unique magnetic properties, such as a lack of hysteresis and a high degree of instability.

How is superparamagnetism different from ferromagnetism?

Ferromagnetism is a well-known phenomenon in which certain materials, such as iron and nickel, exhibit strong permanent magnetization even in the absence of an external magnetic field. Superparamagnetism, on the other hand, only occurs at very small scales and is not a permanent state, as the particles can lose their magnetic properties at higher temperatures.